Hi!
I'm using Freeswitch 1.4.20 (git b95362f 2015-07-03 16:42:15Z 64bit)) (stable one)
and trying to get eavesdropping. But no luck.
Main scheme:
DID - > extension (210). 210 answers
eavesdropping from extension 110.
While giving a command 
eavesdrop <channel-uuid> 
I've got log full of messages 
2015-07-09 13:29:00.325667 [ERR] switch_core_io.c:1531 Write Buffer 0 bytes Failed!
and silence on 110 extension

While giving a command 
userspy 210@${domain_name} or userspy <channel-uuid>
I've got music-on-hold on 110, no errors on log.

In both cases used <channel-uuid> of extension 210 (answered one)

Is this a bug or I'm doing something wrong?
--
Best regards,
Igor