sshd delay

[Andrew Pantyukhin]

I have a problem. When I run sshd -ddd I get this:
(I get the same delay without -ddd, of course)

<...>
debug3: mm_pty_allocate: waiting for MONITOR_ANS_PTY
debug3: mm_request_receive_expect entering: type 26
debug3: mm_request_receive entering
===> <60-90 seconds of delay>
debug3: mm_request_send entering: type 26
<...>

I started getting the delay a few days ago, on a number of
hosts running 6.0-RELEASE/i386. I tried setting UseDNS
off - to no effect. The sshd process is in state sbwait during
the delay. Any ideas?