The European version of WAAS is called EGNOS.
The EGNOS signal has been receivable by handheld GPSs for a few years but IFR (panel mounted) units have bizzarely been prohibited from using it.
However, this has just appeared on some other forums
Dear EGNOS user,
The certification of the ESSP SAS as an Air Navigation Service Provider is progressing according to plan and is expected to be completed by the second half of this year. Once the ESSP SAS is certified as an ANSP, the message type 0 will be removed from the EGNOS Signal in Space. After an initial observation period (around 1 month), the EGNOS Safety of Life service will be declared ready for use. After this milestone, the corresponding ANSPs will begin the publication of GNSS RNAV procedures based on EGNOS, many of them currently under development. Therefore it is expected that several GNSS RNAV procedures will be available for use in Europe before the end of 2010 and many others will follow during early 2011.
Best regards,
The EGNOS Helpdesk