SSL 247 are authorised strategic resellers of Verisign,GlobalSign, Geotrust and RapidSSL products

Your requirements:
You do not need a ‘high assurance’ extended validation (EV) SSL certificate.
You need a wireless-device compatible SSL certificate
You need to secure multiple sub-domains with one certificate (a wildcard SSL certificate)

Wildcard SSL certificates enable you to secure unlimited sub-domains with one SSL certificate, such as the www. and non-www. plus secure.yourdomain.com, extranet.yourdomain.com intranet.yourdomain.com etc.

Wildcards can save you money, as you only need one cert to do unlimited domains, plus you can use your certificate to do x sub-domains now, and add more over the course of its life (ie you don’t have to decide how many sub-domains you are going to secure when you order).