diff --git a/client/clients/Makefile b/client/clients/Makefile
index b62faa0..808ba9e 100644
--- a/client/clients/Makefile
+++ b/client/clients/Makefile
@@ -1,4 +1,3 @@
-CC=cl65
 AS=ca65
 LD=ld65
 CFLAGS=-Oirs -t $(TARGET)
@@ -11,11 +10,6 @@ INCFILES=\
   ../inc/menu.i\
   ../inc/nb65_constants.i\
   
-%.o: %.c
-	$(CC) -c $(CFLAGS) $<
-
-%.o: %.s $(INCFILES) 
-	$(AS) $(AFLAGS) $<
 
 IP65LIB=../ip65/ip65.lib
 
@@ -23,17 +17,30 @@ C64NETLIB=../drivers/c64net.lib
 APPLE2NETLIB=../drivers/apple2net.lib
 
 BOOTA2.PG2=../../server/boot/BOOTA2.PG2
-
   
 all: \
 	rrnetboot.bin \
 	utherboot.dsk \
+	64nicboot.bin  \
 	$(BOOTA2.PG2) \  
-  
+
+rrnetboot.o: rrnetboot.s $(INCFILES)
+	$(AS) -DBANKSWITCH_SUPPORT=2 $(AFLAGS) $<
+
+64nicboot.o: rrnetboot.s $(INCFILES)
+	$(AS) -DBANKSWITCH_SUPPORT=1 $(AFLAGS) -o 64nicboot.o $<
+
+%.o: %.s $(INCFILES) 
+	$(AS) $(AFLAGS) $<
+
 rrnetboot.bin: rrnetboot.o $(IP65LIB) $(C64NETLIB) $(INCFILES) ../cfg/rrbin.cfg
 	$(LD) -m rrnetboot.map -vm -C ../cfg/rrbin.cfg -o rrnetboot.bin  $< $(IP65LIB) $(C64NETLIB)  
-	ruby fix_cart.rb rrnetboot.bin
-  
+	ruby fix_cart.rb rrnetboot.bin 8193
+
+64nicboot.bin: 64nicboot.o $(IP65LIB) $(C64NETLIB) $(INCFILES) ../cfg/rrbin.cfg
+	$(LD) -C ../cfg/rrbin.cfg -o 64nicboot.bin  $< $(IP65LIB) $(C64NETLIB)  
+	ruby fix_cart.rb 64nicboot.bin 8192
+
 utherboot.pg2: utherboot.o $(IP65LIB) $(APPLE2NETLIB) $(INCFILES) ../cfg/a2language_card.cfg
 	$(LD) -m utherboot.map -C ../cfg/a2language_card.cfg -o utherboot.pg2  $< $(IP65LIB) $(APPLE2NETLIB)  
 
@@ -47,6 +54,7 @@ $(BOOTA2.PG2): bootmenu.o $(IP65LIB) $(APPLE2NETLIB) $(INCFILES) ../cfg/a2langua
 clean:
 	rm -f *.o
 	rm -f rrnetboot.bin rrnetboot.map 
+	rm -f 64nicboot.bin 64nicboot.map 
 	rm -f utherboot.pg2 utherboot.map utherboot.dsk
 	rm -f $(BOOTA2.PG2)
 
diff --git a/client/clients/fix_cart.rb b/client/clients/fix_cart.rb
index 88a33a7..2aca81d 100644
--- a/client/clients/fix_cart.rb
+++ b/client/clients/fix_cart.rb
@@ -3,18 +3,24 @@
 # so we want to make sure the bin file is an odd length - specifically 8193 bytes
 #
 
-FILE_LENGTH=8193
+
 PAD_BYTE=0xff.chr
 filename=ARGV[0]
+
 if filename.nil? then
   puts "no filename specified"
   exit
 end
-  
+
+if ARGV[1].nil? then
+  puts "no padding length specified"
+  exit
+end
+file_length=ARGV[1].to_i
 
 infile=File.open(filename,"rb").read
-puts "fixing length of #{filename} from #{infile.length} to #{FILE_LENGTH} bytes"  
+puts "fixing length of #{filename} from #{infile.length} to #{file_length} bytes"  
 outfile=File.open(filename,"wb")
 outfile<<infile
-outfile<<PAD_BYTE*(FILE_LENGTH-infile.length)
+outfile<<PAD_BYTE*(file_length-infile.length)
 outfile.close
\ No newline at end of file
diff --git a/client/clients/rrnetboot.s b/client/clients/rrnetboot.s
index 892790a..6cc5bd5 100644
--- a/client/clients/rrnetboot.s
+++ b/client/clients/rrnetboot.s
@@ -9,6 +9,15 @@
 ; jonno@jamtronix.com - January 2009
 ;
 
+;possible bankswitch values are:
+;$00 = no bankswitching (i.e. NB65 API in RAM only)
+;$01 = standard bankswitching (via HIRAM/LORAM)
+;$02 = advanced bankswitching (via custom registers, e.g. $de00 on the Retro Replay cart)
+
+.ifndef BANKSWITCH_SUPPORT
+  .error "must define BANKSWITCH_SUPPORT"
+  
+.endif 
 
   .macro print_failed
     ldax #failed_msg
@@ -59,8 +68,14 @@
   
   .data
 exit_cart:
+.if (BANKSWITCH_SUPPORT=$01)
   lda #$02    
-  sta $de00   ;turns off RR cartridge - obviously we need to execute this from RAM else we fall into never-never land :-)
+  sta $de00   ;turns off RR cartridge by modifying GROUND and EXROM
+.elseif (BANKSWITCH_SUPPORT=$02)
+  lda #$36
+  sta $0001   ;turns off ordinary cartridge by modifying HIRAM/LORAM (this will also bank out BASIC)
+.endif
+
 call_downloaded_prg: 
    jsr $0000 ;overwritten when we load a file
    jsr $c004 ;bank cartridge in again
@@ -77,7 +92,7 @@ nb65_param_buffer: .res $20
 .byte $C3,$C2,$CD,$38,$30 ; "CBM80"
 .byte $4E,$42,$36,$35  ; "NB65"  - API signature
 .byte $01 ;NB65_API_VERSION
-.byte $02 ;NB65_BANKSWITCH_SUPPORT
+.byte BANKSWITCH_SUPPORT ;
 jmp nb65_dispatcher    ; NB65_DISPATCH_VECTOR   : entry point for NB65 functions
 jmp ip65_process          ;NB65_PERIODIC_PROCESSING_VECTOR : routine to be periodically called to check for arrival of ethernet packects
 jmp timer_vbl_handler     ;NB65_VBL_VECTOR : routine to be called during each vertical blank interrupt
@@ -118,7 +133,14 @@ init:
   ldax #nb65_ram_stub_length
   jsr copymem
 
-  
+;if this is a 'normal' cart then we will end up swapping BASIC out, so copy it to the RAM under ROM
+.if (BANKSWITCH_SUPPORT=$01)
+  ldax #$A000
+  stax copy_src
+  stax copy_dest
+  ldax #$2000
+  jsr copymem
+.endif  
   
   ldax  #startup_msg 
   jsr print
@@ -341,8 +363,15 @@ press_a_key_to_continue:
 
 nb65_ram_stub: ; this gets copied to $C000 so programs can bank in the cartridge
 .byte $4E,$42,$36,$35  ; "NB65"  - API signature
+  
+.if (BANKSWITCH_SUPPORT=$01)
   lda #$01    
   sta $de00   ;turns on RR cartridge (since it will have been banked out when exiting to BASIC)
+.elseif (BANKSWITCH_SUPPORT=$02)
+  lda #$37
+  sta $0001   ;turns on ordinary cartridge by modifying HIRAM/LORAM (this will also bank in BASIC)
+.endif
+
   rts
 nb65_ram_stub_end:
 nb65_ram_stub_length=nb65_ram_stub_end-nb65_ram_stub
\ No newline at end of file
diff --git a/client/ip65/dhcp.s b/client/ip65/dhcp.s
index 5fd6f34..ab90938 100644
--- a/client/ip65/dhcp.s
+++ b/client/ip65/dhcp.s
@@ -10,7 +10,10 @@
 MAX_DHCP_MESSAGES_SENT=12     ;timeout after sending 12 messages will be about 15 seconds (1+2+3...)/4
 
   .include "../inc/common.i"
+.ifndef NB65_API_VERSION_NUMBER
+  .define EQU     =
   .include "../inc/nb65_constants.i"
+.endif
   
   .export dhcp_init
   .import dhcp_server 
diff --git a/client/ip65/dns.s b/client/ip65/dns.s
index ff4fbfd..fb6b7d4 100644
--- a/client/ip65/dns.s
+++ b/client/ip65/dns.s
@@ -3,7 +3,10 @@
   MAX_DNS_MESSAGES_SENT=8     ;timeout after sending 8 messages will be about 7 seconds (1+2+3+4+5+6+7+8)/4
 
 .include "../inc/common.i"
-.include "../inc/nb65_constants.i"
+.ifndef NB65_API_VERSION_NUMBER
+  .define EQU     =
+  .include "../inc/nb65_constants.i"
+.endif
 
   .export dns_set_hostname
   .export dns_resolve
diff --git a/client/ip65/tftp.s b/client/ip65/tftp.s
index 5089d01..c84e69b 100644
--- a/client/ip65/tftp.s
+++ b/client/ip65/tftp.s
@@ -6,8 +6,10 @@
   TFTP_TIMER_MASK=$F8 ;mask lower two bits, means we wait for 8 x1/4 seconds
 
   .include "../inc/common.i"
+.ifndef NB65_API_VERSION_NUMBER
+  .define EQU     =
   .include "../inc/nb65_constants.i"
-
+.endif
 
   .exportzp tftp_filename
   .export tftp_load_address
diff --git a/dist/make_dist.rb b/dist/make_dist.rb
index f7c715e..f691082 100644
--- a/dist/make_dist.rb
+++ b/dist/make_dist.rb
@@ -16,6 +16,7 @@ end
 [
 ["client/clients/utherboot.dsk","client/"],
 ["client/clients/rrnetboot.bin","client/"],
+["client/clients/64nicboot.bin","client/"],
 ["server/lib/tftp_server.rb","lib"],
 ["server/bin/tftp_only_server.rb","bin/tftp_server.rb"],
 ["server/bin/import_ags_games.rb","bin"],