My HTC Tattoo loses its mobile broadband connection after a couple of days without a restart. Calling and SMS still work but no data connections. Disabling and reenabling the mobile data connection does not help. Only with a restart the data connection can be used again. Is there a solution to this problem?

Right now I am using HTC Hero, having firmware Android 2.1 and I have attached VODAFONE, India SIM-CARD in this phone, and also having Wi-fi connectivity. Whenever I try to "sign-in" to Android-Market using Google Account, it is always showing "Can't Establish a reliable data connection to the server" titled error with the message "This could be a temporary problem or your phone may not be provisioned for data services. If it continues, call Customer Care." Now what do I …