g1smd - 11:10 am on Feb 1, 2011 (gmt 0)
The above code will re-append the original query string.
To suppress that action add a question mark to the target URL.
If you want to "re-build" the query string with ? and = the code will be a LOT more complex.
There was a similar question a few weeks ago. That other thread contains a large amount of example code.