Originally Posted by penguin3107
From their FAQ:
Q: Does each instant message sent from WebMessenger constitute a SMS message?
Instant Messages sent from the WebMessenger client do not constitute SMS messages, they use only the data channel, which in fact is used by your e-mails. Therefore, whatever plan you have for your e-mails will be used by WebMessenger IMs.
Read the red bolded section. It does NOT use SMS but uses DATA!