osservices.o error

By installing the softmodem driver I've got following error:

ERROR: Module build failed!
Please examine the log file "/tmp/hsfconfig-buildlog.txt" to determine why.
execution of hsfmodem-7.18.00.03full-1 script failed, exit status 1
ERROR: Installation of the package failed!

Here is my hsfconfig-buidlog.txt file:

rm -rf *.o GPL/*.o *.ko GPL/*.ko *.mod.c GPL/*.mod.c .*.cmd GPL/.*.cmd

GCC -DEXPORT_SYMTAB -o mod_osspec.o mod_osspec.c
In file included from ../modules/include/osresour_ex.h:30,
                 from mod_osspec.c:18:
../modules/imported/include/configtypes.h:1379: warning: unnamed 
struct/union that defines no instances

GCC -o osservices.o osservices.c
osservices.c: In function `cnxt_thread':
osservices.c:438: implicit declaration of function `snprintf'
make: *** [osservices.o] Error 1

And here is the installation log:

./cnxtinstall.run
Verifying archive integrity... All good.
Uncompressing Linux drivers for Conexant modem chipsets Installer 
version 0.9.6

Please ensure that all modems are attached to the machine.
Press enter to continue.

Detecting all PCI and USB devices in your system... please wait...
WARNING: Can't obtain a list of USB devices on this system.
Done.

The following supported device was detected:

Name: Communication controller: CONEXANT: Unknown device 2f00
PCI ID: 14F1:2F00 14F1:2000
Needed package: hsfmodem

The following package will be installed: hsfmodem

Do you want to install this package ([y]/n)?


Conexant HSF softmodem driver Installer version 0.9.6
Copyright (c) 2004-2005 Linuxant inc.

Generating the list of available packages...
Downloading
http://www.linuxant.com/drivers/hsf/full/archive/hsfmodem-latest/archive...
100%

The following package is compatible with your system:
Generic package : hsfmodem-7.18.00.03full-1.i386.rpm.zip

Please enter 'help' if you want more information about pre-compiled vs.
generic packages. Do you want to install this package ([yes]/no/help)?

Downloading
http://www.linuxant.com/drivers/hsf/full/archive/hsfmodem-latest/hsfmodem-7.18.00.03full-1.i386.rpm.zip... 

100%
Installing the package hsfmodem-7.18.00.03full-1.i386.rpm:

Conexant HSF softmodem driver, version 7.18.00.03full

If you need license keys, assistance or more information, please go to:
        http://www.linuxant.com/

When reporting a problem for the first time, please send
us the file generated by "hsfconfig --dumpdiag".
 
No pre-built modules for: SuSE-7.1 linux-2.4.0-4GB i586
 
Trying to automatically build the driver modules...
(this requires a C compiler and proper kernel sources to be installed)
 
WARNING: the kernel version (2.4.0) defined in
/lib/modules/2.4.0-4GB/build/include/linux/version.h
does not match the currently running kernel (2.4.0-4GB)
The cause of this problem is an incorrect kernel source path.
Please check that /lib/modules/2.4.0-4GB/build points to the right tree.
The cause of this is usually a missing or unconfigured
kernel source tree (and sometimes an incorrect directory or symbolic link).
 
Building modules for kernel 2.4.0, using source directory
/lib/modules/2.4.0-4GB/build. Please wait...
 
ERROR: Module build failed!
Please examine the log file "/tmp/hsfconfig-buildlog.txt" to determine why.
execution of hsfmodem-7.18.00.03full-1 script failed, exit status 1
 
ERROR: Installation of the package failed!

Thanks for help, Pascal