removing "link down"

[Manny Tokunaga [c100]]

We have the following problem on our Sun.

System   :   Sun/3 180  Sun OS 4.0.1
Problem  :  /dev/cua* occasionally goes into "link down" mode.
Diagnosis:

 o There is no LCK_* file in /usr/spool/uucp. "tip" | uucp is not running.
 o Modem is working/ready. Power cycling it does nothing.
 o Likely to happen when tip is killed externally by a user (i.e. kill -9)
 o Subsequent tip execution results in "link down" messages from the system.
 o Only way to remove this condition we know of is to reboot the system.

If anybody knows of ways to fix the problem without rebooting the system,
I am very interested in knowing how.  Thank you very much in advance.

Manabu Tokunaga, Imatron Inc. manny at imatron.COM