wondering if this could be answered from drupal's forums. typically dolphin does not play well with other scripts, actually, it does not play well by itself at times.
so looking to include the member_menu on a drupal, where it is possible, it would require some work. though drupals templating system and dolphin's templating system are completely adverse of each other. you would need to custom program this in order to achieve what you are asking. this is not a matter of an iframe, dolphin really dont like iframes, if you have a means of setting a wrapper on drupal, then you may be able to approach it in that manner.
there are no answers to this most likely because those who choose to use dolphin, use dolphin primarily, and dont make any attempts at inter-mingling with drupal, or mambo, or joomla.
if it was that easy, i think there are thousands who have expressed their desire to replace the orca forum, and another set of thousands who would like to replace the lame-o blog with wordpress, or some other intuitive blogging system.
so the answer is, with custom programming, yes, you could do this. the answer is not here in the forums dealing primarily with dolphin specific related issues.
you may find some answers on one of the freelancer sites, and see if you could impart some CMS developer to come up with the methodology you are seeking.
good luck in your ventures.
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