ipmon stopping

Has anyone seen where ipmon intermittently fails? It is running on
Solaris E420, with ipfilter 3.4.33pre1, and writing to syslog:

ipmon -Dasv

One thing I have noticed under lsof is:

ipmon 25163 root 4r VCHR 136,0 0t44206384 229635
/devices/pseudo/ipf@0:ipf
ipmon 25163 root 5r VCHR 136,1 0t243300 229678
/devices/pseudo/ipf@0:ipnat
ipmon 25163 root 6r VCHR 136,2 0t34716612 230122
/devices/pseudo/ipf@0:ipstate

The SIZE/OFF of the ipf devices keeps increasing:
ipmon 25163 root 4r VCHR 136,0 0t46715716 229635
/devices/pseudo/ipf@0:ipf
ipmon 25163 root 5r VCHR 136,1 0t257160 229678
/devices/pseudo/ipf@0:ipnat
ipmon 25163 root 6r VCHR 136,2 0t36649704 230122
/devices/pseudo/ipf@0:ipstate

I'm wondering if when it reaches 0xffffffff it might fail.

Thanks,
Paul

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