Cannot use predictive mode with latex

[Christian Herenz <herenz@physik.hu-berlin.de>]

Hi,

Predictive just will not work on my machine with latex (or html).
I checked everything twice, and then used the debugger as advised in the 
INSTALL file (that comes with predictive).

The following steps laed to the error (after having completed the steps 
in your INSTALL file):
1. C-x f test.tex (file does not exist - new)
2. M-x predictive-mode
3. Enter \ (Backslash - I normally would like to write something like 
"\begin{document}")

Debbugger says following in emacs:
Debugger entered--Lisp error: (wrong-type-argument number-or-marker-p nil)
   =(nil 92)
   (while (= (char-before) 92) (backward-char) (incf i))
   (save-excursion (while (= ... 92) (backward-char) (incf i)))
   (let ((i 0)) (save-excursion (while ... ... ...)) (if (oddp i) (quote 
add) (quote reject)))
   (lambda nil (let (...) (save-excursion ...) (if ... ... ...)))()
   auto-completion-self-insert()
   completion-self-insert()
   call-interactively(completion-self-insert)

4. After that I only hear beeps when I try to modify something in the 
buffer (i.e. it is blocked). I am not able to add anything to the buffer.

I hope I am doing not something completely wrong here, so that it is my 
fault. But I checked everything twice (steps in the install file). Very 
odd (I did just the plain install: make, make install)....

I'm running the Emacs version, which comes with debian lenny:
GNU Emacs 22.2.1 (x86_64-pc-linux-gnu, GTK+ Version 2.12.11) of 
2008-11-09 on excelsior, modified by Debian. But I just tested it an run 
into the same problem on openSUSE 11.1.

When entering predictive-mode in a plain text file, it works fine.

Greetings,
Christian