WLM pauses reacting for more than 1 minute

On our Tablet PCs with XP tablet edition, all versions of WLM, including
the two betas, use to freeze for up to 2 minutes after program start. This
behavior does not depend on auto-signin or no signin.

In particular: after WLM has started and signed in, on a remote PC he is
shown as online, but the remote user has to wait up to 2 minutes before
connecting to him. Otherwise WLM stops reacting for 1 to 3 minutes.

My first suspicion, handwriting tools and MS journalviewer might be
conflicting in some way, can't be true, since we experience the same
trouble on some normal laptops, too.

Any explanation, any workaround? Regards,
Thomas