It seem O2 may not be the only one up to this: Headers that can be used to ident...

It seem O2 may not be the only one up to this:

  Headers that can be used to identify the end user:

  Header name 	 	What it means
  x-drutt-portal-user-msisdn 	The mobile phone number.
  x-h3g-msisdn 	 	the phone number.
  x-imsi: 	 	The imsi number. Identifies the end user.
  x-msisdn 	 	The end users phone number
  x-wsb-identity 	End users phone number
  x-wte-msisdn: 	Indicates that the value is a phone number. Does not look like that...
  x-nokia-imsi: 	Imsi value
  x-nokia-alias 	The end users phone number. encrypted.
  x-nokia-msisdn: 	The users phone number in plain text.
  x-up-calling-line-id: 	End user identifier

Gleaned from: http://mobiforge.mobi/developing/blog/useful-x-headers?dm_sw...

Edit: fixed the formatting.