Those of you that have a BlackBerry Curve 8310, we have some good news for you. It's not a 5.0 OS but a carrier that goes by the name of Sunrise has released OS 4.5.0.181 for the BlackBerry Curve 8310. This is currently the highest official OS for this device.

BlackBerry Curve 8310 Smartphone
BlackBerry Handheld Software v4.5.0.304 (Multilanguage)

Package Version: 4.5.0.304
Consisting of:

• Applications: 4.5.0.181
• Software Platform: 2.7.0.108
• File name: 8310M_PBr4.5.0_rel304_PL2.7.0.108_A4.5.0.181_Sunrise.exe
• File size: 90.99 MB

Note: The Software Platform and Applications version numbers can be found under Options-About screen on the handheld.

• Download Official Release OS 4.5.0.181 from Sunrise