We are on 6.2. I don't believe there is any documented way to pull that off. BladeLogic PS might be able to give you some undocumented commands. For a one off, that might be sufficient, but I wouldn't want to count on those commands if they aren't documented.
Someone on 6.3.x might have additional info.
What are the extended objects that you want to create. Are they closely related?
If they return 40 items of information, you could make just a few extended objects that returns stuff in a Windows ini format, or an xml format.
You can then use stanzas to group the information together.
Does this make sense?
In 6.3.2 there are unreleased blcli commands to create extended objects. To expose this functionality, it would require a BladeLogic resource to create a blcli complex command. Contact your Account Team / Professional Services to discuss how this could be accomodated.