uncaught exception error ....

[thepreacher]

I am stuck on this error that i have no clue about;

"uncaught exception: [Exception... "Component returned failure code: 0x80070057 (NS_ERROR_ILLEGAL_VALUE) [nsIXMLHttpRequest.open]" nsresult: "0x80070057 (NS_ERROR_ILLEGAL_VALUE)" location: "JS frame :: javascript: eval(__firebugTemp__); :: anonymous :: line 1" data: no]"

It pops up when i try to pass a couple of parameters to a php script whic will use them to perform a select.

I appreciate it may not make much sense buta any general explanation will be much appreciated.

Thanks.