On-Access scanning is not running

Hi all,

I have a strange problem and I don't understand what's happening. We have a platform with some debian clients and RHEL clients with a console.

On my console I see that there is a problem with the strategy. It's different with my policy for only RHEL Clients. After some researchs, I found that on-access scanning is not running :

/data/sophos-av/bin/savdstatus
Sophos Anti-Virus is active but on-access scanning is not running

However in my policy, I enable on-access scanning. So, on client I launched :

root@rhel1:~# /data/sophos-av/bin/savdctl enable
root@rhel1:~# /data/sophos-av/bin/savdstatus
Sophos Anti-Virus is active but on-access scanning is not running

And that doesn't work :( .

After others researchs, I found that in talpaselect.log :

Building...
No such file or directory
Traceback (most recent call last):
File "talpa_select.py", line 2057, in _action
File "talpa_select.py", line 1179, in load
File "talpa_select.py", line 958, in select
File "talpa_select.py", line 1665, in select
File "talpa_select.py", line 1853, in build

So I tried to follow :

/search?q= 21711

http://www.sophos.com/en-us/support/knowledgebase/13503.aspx

http://www.sophos.com/en-us/support/knowledgebase/14377.aspx

I installed :

gcc

kernel-devel

I launched : engine/talpa_select select

and now there is that in talpaselect.log :

Building...
No such file or directory
Traceback (most recent call last):
File "talpa_select.py", line 2057, in _action
File "talpa_select.py", line 1179, in load
File "talpa_select.py", line 958, in select
File "talpa_select.py", line 1665, in select
File "talpa_select.py", line 1853, in build
File "/opt/sophos-av/lib/python2.5/subprocess.py", line 444, in call
File "/opt/sophos-av/lib/python2.5/subprocess.py", line 594, in __init__
File "/opt/sophos-av/lib/python2.5/subprocess.py", line 1097, in _execute_child
OSError: [Errno 2] No such file or directory

When I did : 

strace engine/talpa_select select

 I can see (in resume, I think you don't need every line :P ) :

subprocess.py = -1 ENOENT (No such file or directory)

talpa_select.py  = -1 ENOENT (No such file or directory)

For your information, here are RHEL versions :

Red Hat Enterprise Linux Server release 5.9 (Tikanga)

2.6.18-348.6.1.el5 #1 SMP Fri Apr 26 09:21:26 EDT 2013 x86_64 x86_64 x86_64 GNU/Linux

and 

/data/sophos-av/bin/savscan -v | less
SAVScan virus detection utility
Copyright (c) 1989-2013 Sophos Limited. All rights reserved.

System time 10:56:37, System date 05 July 2013

Product version : 4.89.0
Engine version : 3.43.0
Virus data version : 4.90
User interface version : 2.03.043
Platform : Linux/Intel
Released : 13 June 2013

So I have 2 questions :

What's happened on my platform ?

And I'm not sure to understanding the goal of talpa module and how it works. Someone could explain me talpa module please :) ?

I hope I was clear enough. Don't hesitate to ask me more information and sorry for my english.

Thank you in advance for you help.

Wagab