Problems with SMTP / Socket code in Ruby 1.7.2

ruby-talk
1

Does anybody have any clues what is causing this error during an STMP send?
The script seems to get it almost randomly.

Failed: Bad file descriptor
ERROR P4NotifyD: Caught Errno::EBADF: Bad file descriptor
D:/P4Scripts/lib/ruby/1.7/net/protocol.rb:576:in write' D:/P4Scripts/lib/ruby/1.7/net/protocol.rb:576:indo_write’
D:/P4Scripts/lib/ruby/1.7/net/protocol.rb:615:in wpend_in' D:/P4Scripts/lib/ruby/1.7/net/protocol.rb:613:ineach_crlf_line’
D:/P4Scripts/lib/ruby/1.7/net/protocol.rb:645:in adding' D:/P4Scripts/lib/ruby/1.7/net/protocol.rb:668:instep’
D:/P4Scripts/lib/ruby/1.7/net/protocol.rb:668:in `adding’
D:/P4Scripts/lib/ruby/1.7/net/protocol.rb:576: [BUG] rb_sys_fail() - errno == 0
ruby 1.7.2 (2002-07-02) [i386-mswin32]

Thanks,
Patrick Bennett