Tatsuo Ishii <t-ishii@sra.co.jp> writes:
> NOTICE:  ctid (0,5) xmin 645188 xmax 645190 cmin 2 cmax 2
> This is odd too, since xmax > 0 or cmax > 0 should never happen with
> visible tuples, in my understanding.
That's what the docs presently say, but they're in error --- nonzero
xmax could represent a not-yet-committed deleting xact (or one that
did commit, but not in your snapshot); or it could be from a deleting
xact that rolled back. 
I get 
regression=# SELECT myftest(1);
NOTICE:  Error occurred while executing PL/pgSQL function myftest
NOTICE:  line 6 at SQL statement
ERROR:  parser: parse error at or near "ctid"
regression=#
so there's something wrong with the function as posted.
        regards, tom lane