Original commit message from CVS:
allow colons in indentifier names (for jack: " ... !alsa_pcm:out_1 jacksink")
_double [[:digit:]]+"."*[[:digit:]]*
_number {_integer}|{_double}
_boolean "true"|"false"|"TRUE"|"FALSE"
-_identifier [[:alpha:]][[:alnum:]\-_%]*
+_identifier [[:alpha:]][[:alnum:]\-_%:]*
_lconnection ({_identifier}\.)?{_identifier}!
_rconnection !({_identifier}\.)?{_identifier}
_bconnection ({_identifier}\.)?{_identifier}!({_identifier}\.)?{_identifier}