Is this SIP as in RFC 3261?

From http://search.cpan.org/~gaas/URI-1.31/URI.pm

sip:

The sip URI specification is described in sections 19.1 and 25 of RFC 3261. URI objects belonging to the sip scheme support the common, generic, and server methods with the exception of path related sub-components. In addition, they provide two methods to get and set sip parameters: $uri->params_form and $uri->params.

sips:

See sip scheme. Its syntax is the same as sip, but the default port is different.

I also came across this, not sure it will help:
http://compose.labri.fr/documentation/sip/SIP_-_Tools_and_Works.htm