Is ADK 2011 Board like Seeed mega2560 boad compatible with ADK 2012?

Is ADK 2011 Board like Seeed mega2560 boad compatible with ADK 2012? I tried to upload sketch to ADK 2011 board on IDE 1.5.1. But I get error message like "ADK2012.ino:2:21: error: variant.h: No such file or directory" and others.
Have you any idea about this? Thanks