diff -Nur jakarta-jmeter-2.3.1/src/protocol/http/org/apache/jmeter/protocol/http/modifier/URLRewritingModifier.java jakarta-jmeter-2.3.1.fixed/src/protocol/http/org/apache/jmeter/protocol/http/modifier/URLRewritingModifier.java
--- jakarta-jmeter-2.3.1/src/protocol/http/org/apache/jmeter/protocol/http/modifier/URLRewritingModifier.java	2007-11-28 14:11:41.000000000 +0100
+++ jakarta-jmeter-2.3.1.fixed/src/protocol/http/org/apache/jmeter/protocol/http/modifier/URLRewritingModifier.java	2008-04-11 16:00:18.475721127 +0200
@@ -169,7 +169,7 @@
 
 		parameterRegexp = JMeterUtils.getPatternCache().getPattern(
                 // ;sessionid=value
-				"[;\\?&]" + quotedArg + "=([^\"'>&\\s;]*)[&\\s\"'>;]?$?" +  // $NON-NLS-1$
+				"[;\\?&]" + quotedArg + "=([^\"'>&\\s;\\\\]*)[&\\s\"'>;]?$?" +  // $NON-NLS-1$
                 
                 // name="sessionid" value="value"
                 "|\\s[Nn][Aa][Mm][Ee]\\s*=\\s*[\"']" + quotedArg