In a uksort() function, the definition of the user-compare function is something like:

function compare($a,$b) {
   ...
}

In that compare function, $a and $b have null data appended to them.  For example, put this inside the compare function:

   echo urlencode($a);

and you will get something like:

   keyvalue%00

I can solve this by trim()-ing $a and $b all the time, but I think this is more of a bug that should be fixed internally.

- Colin