Internal links do have anchor text influence, and they do pass PR around the site. But I'd say they are not treated "exactly" same as external links. How exactly their treatment differs is a bit of a Google secret, and it also seems to shift around a bit. For example, I'd say many internal links get a lot less individual weight than a single external backlink would, especially if they are in the page template (menus and footer links.)
Be aware that the link: operator only reports a sampling of known links, and that sample shifts. Sometimes it shows you some internals and sometimes not. Google does not give you a full backlink report, and you should not use the link: operator for any kind of conclusive analysis.