Apple published a TechNote related to MagSafe power adapter strain relief issues. As expected by many users, Apple indirectly acknowledges the problem with MagSafe power adapter from MacBook (13" Late 2006), MacBook (13"), MacBook Pro (15" Glossy) and MacBook Pro (17"). This is a good move in the right direction; let's hope that Apple will extend the list of products affected to all hardware using first original MagSafe.
Resolution
Whether your product is in or out-of-warranty, you can take your adapter (you don't need to take the computer) to an Apple-Authorized Service Provider or Apple Retail Store for evaluation, and replacement if necessary. You may be eligible for a replacement adapter free of charge pro