Macports can't recognize xcode version properly

I've tried to run the following command to install "automake" package on my Mac:

MacBook:~ administrator$ sudo port install automake
Password:
Error: The installed version of Xcode (5.1.1) is too old to use on the installed OS version. Version 6.1 or later is recommended on Mac OS X 10.10.
To report a bug, follow the instructions in the guide:
    http://ift.tt/S1xIPz
Error: Processing of port automake failed

The problem is in the line:

Error: The installed version of Xcode (5.1.1) is too old to use on the installed OS version. Version 6.1 or later is recommended on Mac OS X 10.10.

But there is xcode 6.1 installed on my mac. Note that i'm using MacOS 10.10 yosemite(macports for 10.10 already installed). Please help me