Timeout::Error (execution expired)

I’ve been constantly getting in the recent days:
Timeout::Error (execution expired):
/usr/lib/ruby/1.8/timeout.rb:54:in new' /usr/lib/ruby/1.8/net/protocol.rb:206:inold_open’
/usr/lib/ruby/1.8/timeout.rb:56:in timeout' /usr/lib/ruby/1.8/timeout.rb:76:intimeout’

This has started one or two days ago, and never before. It is happening
on
various locations that most certainly should not take too long to
execute.(and again, it never happened before)
Is there a standard reason for this to happen?

Bogdan