diff --git a/SheepShaver/src/kpx_cpu/src/cpu/ppc/ppc-execute.cpp b/SheepShaver/src/kpx_cpu/src/cpu/ppc/ppc-execute.cpp
index fe2c727e..26e98533 100644
--- a/SheepShaver/src/kpx_cpu/src/cpu/ppc/ppc-execute.cpp
+++ b/SheepShaver/src/kpx_cpu/src/cpu/ppc/ppc-execute.cpp
@@ -37,6 +37,7 @@
 
 #ifdef SHEEPSHAVER
 #include "main.h"
+#include "prefs.h"
 #endif
 
 #if ENABLE_MON
@@ -54,6 +55,14 @@
 void powerpc_cpu::execute_illegal(uint32 opcode)
 {
 	fprintf(stderr, "Illegal instruction at %08x, opcode = %08x\n", pc(), opcode);
+
+#ifdef SHEEPSHAVER
+	if (PrefsFindBool("ignoreillegal")) {
+		increment_pc(4);
+		return;
+	}
+#endif
+
 #if ENABLE_MON
 	disass_ppc(stdout, pc(), opcode);
 
diff --git a/SheepShaver/src/prefs_items.cpp b/SheepShaver/src/prefs_items.cpp
index bf03be28..1d4758dc 100644
--- a/SheepShaver/src/prefs_items.cpp
+++ b/SheepShaver/src/prefs_items.cpp
@@ -54,6 +54,7 @@ prefs_desc common_prefs_items[] = {
 	{"nogui", TYPE_BOOLEAN, false,      "disable GUI"},
 	{"noclipconversion", TYPE_BOOLEAN, false, "don't convert clipboard contents"},
 	{"ignoresegv", TYPE_BOOLEAN, false, "ignore illegal memory accesses"},
+	{"ignoreillegal", TYPE_BOOLEAN, false, "ignore illegal instructions"},
 	{"jit", TYPE_BOOLEAN, false,        "enable JIT compiler"},
 	{"jit68k", TYPE_BOOLEAN, false,     "enable 68k DR emulator"},
 	{"keyboardtype", TYPE_INT32, false, "hardware keyboard type"},
@@ -80,6 +81,7 @@ void AddPrefsDefaults(void)
 	PrefsAddBool("nogui", false);
 	PrefsAddBool("noclipconversion", false);
 	PrefsAddBool("ignoresegv", false);
+	PrefsAddBool("ignoreillegal", false);
 
 #if USE_JIT
 	// JIT compiler specific options
@@ -89,5 +91,5 @@ void AddPrefsDefaults(void)
 #endif
 	PrefsAddBool("jit68k", false);
 
-    PrefsAddInt32("keyboardtype", 5);
+	PrefsAddInt32("keyboardtype", 5);
 }