iBCS broken with 2.2.19

[Mike Barton <mike@dad.state.vt.us>]

ibcs-2.1-981105 compiles and works find with 2.2.18 but with 2.2.19 this
happens:

pogo:/usr/src# modprobe iBCS
/lib/modules/2.2.19/misc/iBCS: unresolved symbol strlen_user
/lib/modules/2.2.19/misc/iBCS: insmod /lib/modules/2.2.19/misc/iBCS failed
/lib/modules/2.2.19/misc/iBCS: insmod iBCS failed

Any pointers greatly appreciated.