Portal link on logon screen, link should acess some extrnl portal component

Hi all,

Can you please help with my issue.

I have web service implemenation in PDK or Webdynpro which verifies the staff details.

I need to integrate this application in portal logon screen link, as replacement to getsupportor login problems.

if users clicks on this link, he should be redirected to that portal component without asking the logon credentials.

Any technical help is appreciated