Improved handling of missing bonjour support

Ignore-this: b750c36b2b936106236db74cac2b75fd

darcs-hash:20100701090614-1e3d8-7ad5d977e3665cadb5c1609db251409e866760da
Simplified test

Ignore-this: f13e7a1b32dc6720aa5c7b4bb92d02fb

darcs-hash:20100702063949-1e3d8-13662711d6747df64b8059eb210cdf35b0bdb9eb