It looks like ipmitool limits hostname length to 64 symbols.
If hostname is longer than 64 symbols tool hangs unexpected:
$ ipmitool -U ADMIN -P ADMIN -H 123456789-123456789-123456789-123456789-123456789-123456789.ffix.org lan print
Address lookup for 123456789-123456789-123456789-123456789-123456789-123456789.ffixADMIN failed
Could not open socket!
I attached the patch to work around the issue.
Yes, some fixing is needed, but your patch is IMHO wrong. NACK.
On a second though, it really might be the easiest solution to the problem at hand. sigh
This has been addressed by https://sourceforge.net/p/ipmitool/bugs/277/