Hi Monu,
The only rule if this one : "If you're taking Sun's new exam, please prefix your message subjects with 'NX:'". Now the "new" assignments are not so new anymore, in such a way that posts of candidates who got some "old" assignment become the exception on this forum. Anyway, it's still "the" rule.
If your question is general (and many questions are because assignments are quite similar), I wouldn't care about telling your specific assignment. If you think your question is specific to URLyBird, you may mention "URLyBird" in the title.
Regards,
Phil.