showthread.php?t and showthread.php?p

[jscieza]

Hello,

I notice that some threads are indexed by Google using the showthread.php?t format and other threads are indexed using the showthread.php?p format. It's possible that Google index the same thread using both format? If so, then it will be a duplicate content issue, right?

For example:

http://www.forosperu.net/showthread.php?t=24813 (not indexed by Google... why?)
http://www.forosperu.net/showthread.php?p=309331 (indexed by Google)

Could you please tell me more about that? I don't know much about forum SEO.

Thank you!
Jonathan.