RadUpload problem with firefox

Q:

I use RadUpload Telerik control to upload more than image ..this control is flexible and amazing one.. it works perfectly but recently i find the following problem ::

the problem appear开发者_JS百科s only in firefox not IE

when click on Select button in this control to select my file the button doesn't work at all ,,but when i click on the textbox(which the file path appear in)it opens the window which i can select a file from it .. i don't know what is the problem with firefox .. i wanna the default behavior to not confuse the user ,i wanna when clicking on Select button , showing a window to select my file from it like IE..

any suggestions to fix this problem please...

Might be some kind of z-index and containers overlapping issue, check the html of the page to track it. The ajax upload demos on the telerik site does not suffer from this issue under FireFox, I checked it.