Linux and vpnclient-linux-4.0.3.B-k9 install problem

Has anyone had trouble compiling the linux cisco vpn client? Here is
the output of the install script:

# uname -rviosm
Linux 2.4.22-1.2188.nptl #1 Wed Apr 21 20:19:18 EDT 2004 x86_64 x86_64
GNU/Linux

../vpn_install
Cisco Systems VPN Client Version 4.0.3 (B) Linux Installer
Copyright (C) 1998-2001 Cisco Systems, Inc. All Rights Reserved.

By installing this product you agree that you have read the
license.txt file (The VPN Client license) and will comply with
its terms.


Directory where binaries will be installed [/usr/local/bin]

Automatically start the VPN service at boot time [yes]

In order to build the VPN kernel module, you must have the
kernel headers for the version of the kernel you are running.

For RedHat 6.x users these files are installed in /usr/src/linux by
default
For RedHat 7.x users these files are installed in /usr/src/linux-2.4
by default
For Suse 7.3 users these files are installed in
/usr/src/linux-2.4.10.SuSE by de fault

Directory containing linux kernel source code
[/lib/modules/2.4.22-1.2188.nptl/b uild]

* Binaries will be installed in "/usr/local/bin".
* Modules will be installed in
"/lib/modules/2.4.22-1.2188.nptl/CiscoVPN".
* The VPN service will be started AUTOMATICALLY at boot time.
* Kernel source from "/lib/modules/2.4.22-1.2188.nptl/build" will be
used to bui ld the module.

Is the above correct [y] y

Making module
In file included from Cniapi.h:15,
from linuxcniapi.c:24:
GenDefs.h:101:2: warning: #warning 64 bit
In file included from Cniapi.h:15,
from linuxcniapi.c:24:
GenDefs.h:102: error: syntax error before "intptr_t"
GenDefs.h:102: warning: data definition has no type or storage class
GenDefs.h:111:2: warning: #warning 64 bit
In file included from Cniapi.h:15,
from interceptor.c:30:
GenDefs.h:101:2: warning: #warning 64 bit
In file included from Cniapi.h:15,
from interceptor.c:30:
GenDefs.h:102: error: syntax error before "intptr_t"
GenDefs.h:102: warning: data definition has no type or storage class
GenDefs.h:111:2: warning: #warning 64 bit
In file included from IPSecDrvOS_linux.c:20:
GenDefs.h:101:2: warning: #warning 64 bit
In file included from IPSecDrvOS_linux.c:20:
GenDefs.h:102: error: syntax error before "intptr_t"
GenDefs.h:102: warning: data definition has no type or storage class
GenDefs.h:111:2: warning: #warning 64 bit
In file included from Cniapi.h:15,
from frag.c:16:
GenDefs.h:101:2: warning: #warning 64 bit
In file included from Cniapi.h:15,
from frag.c:16:
GenDefs.h:102: error: syntax error before "intptr_t"
GenDefs.h:102: warning: data definition has no type or storage class
GenDefs.h:111:2: warning: #warning 64 bit
ld: cannot open frag.o: No such file or directory
Failed to make module "cisco_ipsec".