Quality is delighting customers
I guess you should just reopen it and again assign it to the developer team.
For any reason the developer might not be able to reproduce the bug or doesn't get what you wonna tell him.
I normally have a discussion with the developers and tell them why I think that the Issue I raised is a bug.
Either they accept it as a bug (and will fix it) or they can explain/convince me why it "works as designed".
It depends on the timing. When was the status changed to "Rejected"? When was it observed that the issue is still reproducible? If it was some builds ago, then its always good to open a new one. If it was the last build, then its good to reopen the defect.
However, if the defect has had more than 10 threads of comments, (regardless of how recently the defect was opened), I always advise my team to open a brand new defect because the developers easily get confused and lost in the long trail of previous comments....
I agrre with you Behboob.
@Rama: A rejected bug is always accompanied by a reason. If it is 'works as per designed' or 'cannot be resolved', 'change in requirements' etc., then you should not reopen it. If it is 'cannot reproduce', then you can reopen it by giving necessary steps to reproduce.