None of the HD DVD players can handle 25p/50hz HD content at this time, no. Whether the A1 and XA1 will be able to in future I do not know, but the A2/E1 and XA2/XE1 will be getting an update by the spring that adds support for 25p/50hz content.

Microsoft and Toshiba have together been able to persuade content providers to stick with 24p for all 24fps film based content in Europe however so 50hz encodes will only see light of day with content that is 25fps/25p at source, like a lot of BBCs HD content for example.