PM others?

How can I PM on the app it won't let me get to their personal page

Go to any other post that has at least one reply.
Do a fakie reply to that post.
Where it tells you to alternatively use the full website, click that.
This will also enable you to PM folks that do not have an avatar to click on.
You must have your email account set up on your phone in order for this to work properly.
Good luck :p
Edit
PM Sent