/var/log/messages:

kernel BUG at page_alloc.c:81! 
invalid operand: 0000 
CPU:    1 
EIP:    0010:[__free_pages_ok+168/780] 
EFLAGS: 00210282 
eax: 0000001f   ebx: c1af144c   ecx: 00200046   edx: 00000001 
esi: 000000df   edi: e900fc24   ebp: 00000000   esp: ddccfecc 
ds: 0018   es: 0018   ss: 0018 
Process rm (pid: 2695, stackpage=ddccf000) 
Stack: c022c36a c022c3fe 00000051 c1af144c 000000df e900fc24 00000000 00000000  
       c1af144c c1af144c c0123e33 c1af144c c012d1ef c012409a c1af144c ddccff40  
       e900fc2c e900fc24 e900fc34 df01d840 c1af144c ddccff40 c0124168 e900fb80  
Call Trace: [remove_inode_page+59/72] [__free_pages+27/28] [truncate_list_pages+322/436] [truncate_inode_pages+92/148] [iput+162/360] [d_delete+98/160] [vfs_unlink+377/428]  
       [sys_unlink+166/280] [system_call+51/56]  
 
Code: 0f 0b 83 c4 0c 8d 76 00 8b 43 18 a8 20 74 19 6a 53 68 fe c3


ksymoops:

Code;  00000000 Before first symbol
00000000 <_EIP>:
Code;  00000000 Before first symbol
   0:   0f 0b                     ud2a   
Code;  00000002 Before first symbol
   2:   83 c4 0c                  add    $0xc,%esp
Code;  00000005 Before first symbol
   5:   8d 76 00                  lea    0x0(%esi),%esi
Code;  00000008 Before first symbol
   8:   8b 43 18                  mov    0x18(%ebx),%eax
Code;  0000000b Before first symbol
   b:   a8 20                     test   $0x20,%al
Code;  0000000d Before first symbol
   d:   74 19                     je     28 <_EIP+0x28> 00000028 Before first symbol
Code;  0000000f Before first symbol
   f:   6a 53                     push   $0x53
Code;  00000011 Before first symbol
  11:   68 fe c3 00 00            push   $0xc3fe


/usr/src/linux-2.4/scripts/ver_linux:

If some fields are empty or look unusual you may have an old version.
Compare to the current minimal requirements in Documentation/Changes.
 
Linux jim.imdb.com 2.4.5 #20 SMP Sat May 26 09:11:38 BST 2001 i686 unknown
 
Gnu C                  egcs-2.91.66
Gnu make               3.78.1
binutils               2.9.5.0.22
util-linux             2.10p
mount                  2.10r
modutils               2.4.2
e2fsprogs              1.19
PPP                    2.4.0
Linux C Library        2.1.3
Dynamic linker (ldd)   2.1.3
Procps                 2.0.6
Net-tools              1.54
Console-tools          0.3.3
Sh-utils               2.0
Modules Loaded         bsd_comp ppp_async ppp_generic slhc ipchains tdfx w83781d eeprom sensors i2c-isa i2c-piix4 i2c-core via-rhine de4x5 es1371 ac97_codec