(!irpfind) Is This a bug or I don't know how to use it???

Hi,
if I give data(mdlprocess) as 0x856e8248 why is it taking as
0xf73d68d0???
-Srin

kd> !irpfind 0 0 mdlprocess 0x856e8248
Looking for IRPs with mdl process == f73d68d0
unable to get large pool allocation table - either wrong symbols or pool
tagging is disabled

Searching NonPaged pool (8164e000 : 86400000) for Tag: Irp?

Searching NonPaged pool (f7c5b000 : ffbe0000) for Tag: Irp?