WMWifi and data usage

[ruffems]

I have a friend who I sold my TP2 to. She does not have internet where she lives. She's been told it would cost to much to drop a cable to her neighborhood.

So she is left with connecting to the internet via her touch pro 2.

She refuses to allow mightymike's rom on her phone cause it would void her brand new TP2 warranty.

I have tentatively set up her phone to use WMWifi as her internet connection.

What she is very worried about is this
She says she has the unlimited data usage from Sprint but as we all know unlimited to sprint is different than my definition or unlimited.

Will sprint be able to track her data usage via her use of WMWifi or is WMWifi sort of like a stealth connection?

I sold her the phone on the grounds that she should be able to connect to the net which I did but she is insistent that she get's unlimited internet.

I'm relying on the experts here who have experience with this program and it's pitfalls.

Thanks.