Your lens does sound like it could be dirty! Simply wipe it down with a microfiber cloth to remove any grease or dirt that has built up. If you think it's not a cleanliness issue, check out other symptoms [[Blackberry 8110 Troubleshooting#Section_Issues_with_your_camera|here]]. In the case where you need to replace the camera, you can find a guide on how to do that [guide|30450|here]!