I too want 2 know about this
Posting Messages in players homepage

Check out the FAQ on invitations. The following is the most pertinent part:
Please do not use site messages to invite people to your group or team. If you do, your account could be flagged as a spam account.
While I think that primarily is related to the main messaging system on the site, it possibly could include notes. Best bet is to send the invites via the method in the FAQ, as that is the way suggested by the site.

but is it called spaming , if we invite the members of our own group for team matches via personal message

Check out the FAQ on invitations. The following is the most pertinent part:
Please do not use site messages to invite people to your group or team. If you do, your account could be flagged as a spam account.
While I think that primarily is related to the main messaging system on the site, it possibly could include notes. Best bet is to send the invites via the method in the FAQ, as that is the way suggested by the site.
Thanks Martin, I am not speaking about inviting players to join the group, it is joining the team match

Oh, sorry. I misread that. Since they are already part of your team it might be acceptable but I can't say for sure what the site stance would be on it. I would think the best way would be to use the group/team forums and news.
Maybe a staff member will stop by and answer. If it is really important, you might use the contact form on the help page or use the live support available there to ask.
Hello,
Can some one let me know inviting players to join team matches in their home page is considered as spam and will my account will be closed?