Blackberry Java Error Repair

hi guys,
pls does anyone know who or where i can fix my blackberry phone that's malfunctioned and simply puts a message: Uncaught exception: java.lang.ClassCastException.
since this happened, none of the buttons are functioning anyone.
tx,
cheers.

hello,
tx 4 your response.
model of phone is Blackberry 7130g.
not sure of the firmware though, but i can see stuff like;
IC:2503A-RBA 40GW
FCC ID: L6ARBA 40GW
BT MAC: 00 0F 86 4E FE F9
Patents: www.rim.net/patents
IMEI: 359885001217729

CE0168