RTSC Platform Wizard doesn't work with GCC

I'm working on vayu board (Vision High 28) / CortexA15 using GNU compiler.
Since I have to build my own RTCS platform I used the platform wizard. For the original platform everything works, the modified platform produces the following linker error.

c:/ti/ccsv5/tools/compiler/gcc-arm-none-eabi-4_7-2012q4/bin/../lib/gcc/arm-none-eabi/4.7.3/../../../../arm-none-eabi/bin/ld.exe:./configPkg/linker.cmd:14: warning: memory region `EXT_RAM' not declared
c:/ti/ccsv5/tools/compiler/gcc-arm-none-eabi-4_7-2012q4/bin/../lib/gcc/arm-none-eabi/4.7.3/../../../../arm-none-eabi/bin/ld.exe: .gnu.attributes not found for insert

The problem can simply reproduced executing the following steps.

1. Create GNU project: SYS/BIOS->GNU Target Examples->Typical
2. File -> New -> Other... -> Edit/View RTSC Platform
3. Package Name = ti.platforms.evmDRA7XX
4. CPU Core GPP
5. Press "Next"
6. Select "EXT_RAM" for all memory sections
7. Press "Finish"

The "new" platform (nothing was changed compared to the original one) produces the error above when linking.

Here's a list of the relevant tool versions I'm using:

• Code Composer Studio Version 5.5.0.00077
• GCC ARM Compiler Tools 4.7.2012.12
• XDCTools 3.25.3.72

Thanks in advance for any helping answer (I'm currently blocked because of theat issue).

Kind regards,
Roland