OpenSSL feeds your private key to the system PRNG
opensslrampage.org
opensslrampage.org
In short, if there's not enough seed data in the system PRNG (or whatever random subsystem is hooked up), it dumps in your private key in an attempt to increase entropy.
Removed today: http://www.openbsd.org/cgi-bin/cvsweb/src/lib/libssl/src/cry...