Can't compile 64 Bit, Midaslib

I have an application that compiles fine in 32 bit,   but when I try to compile for 64 bit platform I get this error:

[dcc64 Fatal Error] prPsoftSalesManager.dpr(69): F2048 Bad unit format: 'MidasLib.dcu' - Expected version: 31.0, Windows Unicode(x64) Found version: 31.0, Windows Unicode(x86)

I looked online, but I can't find a solution.