Hi Oxwall
“www.researchgate.net” (and linkedin.com) have a important feature for user “Import muliple email Ids, autometic invitation to all ids and autometic follow up for joining the group”.
Is it possible for your software?
e.g.:
http://help.researchgate.net/Researchers
Invite colleagues using their e-mail addresses
ResearchGATE has developed a smart import engine that allows users to paste e-mail addresses separated by commas, enters, or other delimiters. Or use the following workflow: Go to Outlook or other e-mail application and select the contacts you want to import. Copy the entire content into the invite box. You will now see largely unformatted data. Our engine automatically extracts the e-mail addresses from this data and will offer you these for an invitation.
Invite colleagues from your address book
Import your entire Outlook (or other *.csv file) or your Thunderbird address book into ResearchGATE by using this option.