'$',# is not encoded in URL

Hi,

While using '$' in parameter value it is not encoded in the URL and it throws the following exception in SoapUI Pro 4.0.1. But works fine in SoapUI 3.6.1.

Mon Feb 20 02:40:38 EST 2012:ERROR:Exception in request: java.lang.IllegalArgumentException: Illegal group reference
Mon Feb 20 02:40:38 EST 2012:ERROR:An error occured [Illegal group reference], see error log for details
Mon Feb 20 02:40:38 EST 2012:INFO:Error getting response for [xxxxxx/xxxxxxx/xxxxxx/{Id}:ASCII - ~!@#$%^*()_+]; java.lang.IllegalArgumentException: Illegal group reference

Example :
Resource : xxxxxx/xxxxx/xxxxx/{Id}

Case 1 : Id = #$%
Expected : xxxxxx/xxxxx/xxxxx/%23%24%25
SoapUI Pro 4.0.1 - Actual : Unable to read Raw data, the above exception is occurred.
SoapUI 3.6.1 - Actual : /xxxxx/xxxx/%23%24%25

Case 2 : Id = 123$123
Expected : xxxxxx/xxxxx/xxxxx/123%24123
SoapUI Pro 4.0.1 - Actual : Unable to read Raw data
SoapUI 3.6.1 - Actual : /xxxxx/xxxx/123%24123

Case 3 : Id = 123\$123
Expected : xxxxxx/xxxxx/xxxxx/123%5C%24123
SoapUI Pro 4.0.1 - Actual : /xxxxx/xxxx/123$123
SoapUI 3.6.1 - Actual : /xxxxx/xxxx/123%5C%24123

Case 4 : Id = 123#123
Expected : xxxxxx/xxxxx/xxxxx/123%23123
SoapUI Pro 4.0.1 - Actual : /xxxxx/xxxx/123
SoapUI 3.6.1 - Actual : /xxxxx/xxxx/123%23123

Case 5 : Id = #123
Expected : xxxxxx/xxxxx/xxxxx/%23123
SoapUI Pro 4.0.1 - Actual : /xxxxx/xxxx/
SoapUI 3.6.1 - Actual : /xxxxx/xxxx/%23123

Kindly Let me know is this bug. Can I have any work around for this ?

Tested in the following versions

SoapUI 3.6.1 Build dist-111-2010-10-18, Build Date 2010/10/18 14:57
SoapUI Pro 4.0.1 Build dist-142-2011-09-14, Build Date 2011/09/14 13:38

Thanks,
Siva