[pdftex] Pls explain to me: Warning: pdflatex (file f7b6d320.enc): cannot open encoding file for reading

[Mario]

Hello,

I am getting the  warning msg in the subject. I have not idea on what that 
mean (I am just a user).

I am trying to write a php script which let me modify a latex text.tex 
source and output a corrected text.pdf file. The same script works on Win32 
(98) (with the relevant changes on handling files).

On Linux (on a remote server, I believe it is RedHat 9.0) I get the warning:
Warning: pdflatex (file f7b6d320.enc): cannot open encoding file for reading

The .pdf file is output, but it is empty.

Any comment/advise is welcome. Pointers to a (self-explanatory) tutorial 
and/or manual pages is very fine too.
Thanks
mario