diff --git a/build/ACBuild-default.properties b/build/ACBuild-default.properties
index 173afdc..64db587 100644
--- a/build/ACBuild-default.properties
+++ b/build/ACBuild-default.properties
@@ -7,7 +7,9 @@
 #
 swtJarPathWin=C:/Program Files/Eclipse 2.1.x/plugins/org.eclipse.swt.win32_2.1.3/ws/win32/swt.jar
 swtJarPathMac=/Users/Shared/eclipse/plugins/org.eclipse.swt.carbon.macosx_3.3.3.v3349.jar
+swtJarPathUnix=/usr/share/java/swt.jar
 junitPathWin=C:/Java/lib/junit3.8.1/junit.jar
 junitPathMac=/Users/Shared/eclipse/plugins/org.junit_3.8.2.v200706111738/junit.jar
+junitPathUnix=/usr/share/java/junit.jar
 keyconf=${user.home}/.secret
-alias=name
\ No newline at end of file
+alias=name
diff --git a/build/build.xml b/build/build.xml
old mode 100644
new mode 100755
index 7f00836..85a126b
--- a/build/build.xml
+++ b/build/build.xml
@@ -15,16 +15,41 @@
 	<property name="builddir" value="${basedir}/build" />
 	<property file="${builddir}/ACBuild.properties"/>
 	<property file="${builddir}/ACBuild-default.properties"/>
-	<condition property="swtjar"
-		value="${swtJarPathWin}"
-		else="${swtJarPathMac}">
-		<os family="windows"/>
-	</condition>	
-	<condition property="junitjar"
-		value="${junitPathWin}"
-		else="${junitPathMac}">
-		<os family="windows"/>
-	</condition>	
+	<condition property="isWin" value="true">
+		<os family="windows" />
+	</condition>
+	<condition property="isMac" value="true">
+		<and>
+			<os family="mac" />
+			<os family="unix" />
+		</and>
+	</condition>
+	<condition property="isUnix" value="true">
+		<and>
+			<os family="unix" />
+			<not>
+				<os family="mac" />
+			</not>
+		</and>
+	</condition>
+	<condition property="swtjar" value="${swtJarPathWin}">
+		<isset property="isWin" />
+	</condition>
+	<condition property="swtjar" value="${swtJarPathMac}">
+		<isset property="isMac" />
+	</condition>
+	<condition property="swtjar" value="${swtJarPathUnix}">
+		<isset property="isUnix" />
+	</condition>
+	<condition property="juintjar" value="${junitPathWin}">
+		<isset property="isWin" />
+	</condition>
+	<condition property="juintjar" value="${junitPathMac}">
+		<isset property="isMac" />
+	</condition>
+	<condition property="juintjar" value="${junitPathUnix}">
+		<isset property="isUnix" />
+	</condition>
 	<condition property="signing-needed">
 		<available file="${keyconf}" property="keyconf-exists" />
 	</condition>
@@ -203,4 +228,4 @@
 	        <zipfileset dir="${javadoc}" prefix="javadoc"/>
 	    </zip>
 	</target>
-</project>
\ No newline at end of file
+</project>