AMS 5.0.3 abort (failed to create IPC queue __FCS__ : Failed to allocate shared memory)

[santinod]

version: Adobe Media Server 5.0.3 r3029 x64 on Linux

My server apparently runs OK, although the core.*.log are filled with warnings:

2013-10-24      00:00:33    3391    (w)2581227    Shared memory heap (__FCS__) has exceeded 90 usage. Consider increasing the heap size to prevent future memory allocation failures.    -

However, when trying to restart it, the server aborts. This is what gets logged in master.00.log:

2013-10-30      05:25:15        60721   (e)2781340      Process 60721 failed to create IPC queue __FCS__ : Failed to allocate shared memory.    -
2013-10-30      05:25:15        60721   (e)2571122      Server aborted. -

How can I increment the heap size? Will it prevent the restart failure?