How to configure CVSup supfile for correct ports tree ?

[edward]

Hi all,
I just upgraded a 5.3-RELEASE system into 5.4-STABLE using CVSup and the 
usual building procedure. For this, I created a src-supfile containing :
*default tag=RELENG_5
It all went fine and 5.4-STABLE is up and running.
I also have a previously configured ports-supfile with :
*default tag=.
I undestand this points CVSup towards the FreeBSD-current ports collection.
I am concerned about getting software that really matches the version of 
FreeBSD I am running. Is my ports-supfile OK, or should I change the tag 
line to :
*default tag=RELENG_5
to be sure ports and OS are fully compatible ?
Thanks for your insight on this.
Edward