Inability to cast regclass is too restrictive

Release 8.0.0.0beta3

I tried to use regclass() in a plpgsql function to derive a tablename
from its oid so as to build a command string, but I am unable to use the
value returned because it cannot be cast to anything.  Therefore I will
have to use a complex query on the catalog to do the same work.

This seems overly restrictive.  Would there be a problem in allowing
regclass() to be cast to text?

-- 
Oliver Elphick                                          olly@lfix.co.uk
Isle of Wight                              http://www.lfix.co.uk/oliver
GPG: 1024D/A54310EA  92C8 39E7 280E 3631 3F0E  1EC0 5664 7A2F A543 10EA
========================================   "Let no man say when he is tempted, I am tempted of      God; for God cannot
betempted with evil, neither      tempteth he any man; But every man is tempted, when he     is drawn away of his own
lust,and enticed."                                                James 1:13,14