svn revision 379837 removed the date from the net-p2p/bitcoin entry.
Tools like pkg-updating(1) pick up both entries if you have lang/ruby19 installed.
A commit references this bug:
Date: Thu Feb 26 08:08:57 UTC 2015
New revision: 379989
Readd the date removed in last commit
Submitted by: email@example.com
Fixed, thank you for reporting