Have you Noticed USB Mounting's Gone?
Well without further Adue (Or whatever it is)
How to Fix your USB Mounting
Your Device is Probably already Rooted so follow these steps.
1) Download EStrongs File Explorer from the android market.
2) Also Download A Pulse Mini Rom (e.g. GMOD, Stock Rom) (You probably already have one downloaded)
2i) If you don't want to download a Rom, Download this instead (Probably Best to download on the Phone) (Then go to step 4)
3) Open the Rom on your PC, Find the Data Folder then Copy The cdrom folder to the sd card (via e.g SD Reader, Bluetooth)
4) Find the cdrom folder on the phone, using ES File Explorer (or if you downloaded autorun.iso, find it create a Folder named cdrom (no Caps)) Now Copy or Cut the Folder.
5) Then in EStrongs File Explorer Press Menu>Settings>Root Options, Then Check Both Options and when asked choose HiAPK as the Custom Rom.
6)Go back Twice and Press / in the Top left corner
7)Open Data and Paste cdrom the Folder.
All done! Connect Your USB and give it a try.
This works fine with me, but I suspect it might not work with all, But Hey no harm done in trying.