eboard is quite primarily used as a gateway to Internet Chess; FICS, etc.
It is quite important to have timeseal installed for playing any blitz or lightning there, or one is at a great disadvantage. Please consider installing the timeseal functionality by default, to not have users have to do it, and those Gentoo users that don't know about it to not be at a great playing disadvantage over Windows clients and perhaps other distribution users.
Timeseal installation is described at http://www.bergo.eng.br/eboard/doc.php?d=3
Got a patch?
A patch would be extremely simple -- just a flag (hmm... "timeseal"?) to copy http://www.freechess.org/Download/timeseal (a binary) to /usr/share/games/eboard/timeseal.Linux on x86 and amd64.