error loading the pdiff package



I am using maxima 5.9.1 shipped with debian sid.

1) In maxima if I do

load("pdiff.lisp")

the window hangs.

2) If I do the same thing in texmacs, I get

Load failed for /usr/share/maxima/5.9.1/src/mactex.lisp

 -- an error. \ Quitting. \ To debug this try DEBUGMODE(TRUE);

$locate pdiff.lisp
/usr/share/maxima/5.9.1/share/contrib/pdiff/pdiff.lisp

So when I tried the load command with the full path name inside texmacs,

  load("/usr/share/maxima/5.9.1/share/contrib/pdiff/pdiff.lisp")

I got

Load failed for /usr/share/maxima/5.9.1/src/mactex.lisp

 -- an error. \ Quitting. \ To debug this try DEBUGMODE(TRUE);

Any ideas on where I am going wrong?

thanks in advance
raju