[tex-live] cslatex not working / pdfcslatex working ?

[Karl Berry]

    \Gm at checkdrivers ...fined \else \ifnum \pdfoutput

In what file does this code appear?  (Sorry, I can't balance the parens
in the transcript backwards and be sure.)  And what does the surrounding
code look like?

The error rather looks like something is getting expanded when it
shouldn't be, but it's hard to say anything for sure from this fragment.

In TL 2005, \pdfoutput is defined as 0 in dvi-output latex's.  In all
previous years, it has been undefined.  Perhaps that is somehow related
to the error. 

    I've found out that pdfcslatex and cslatex are symlinked to the same  
    binary...and I'm even more perplexed :)

pdftex (the program) can output dvi just fine.  It's always been able
to.  It retains all of the original tex.

Best,
k