'Protocol not supported' on linux socket call ( r313313 amd64 )

[Oleg V. Nauman]

 After upgrading of current on amd64 box to r313313 I noticed that skype has 
stopped working.
 Below is the end of 'truss' output for skype:

36723: linux_socketcall(1,{ LINUX_SOCKET, 0x0 }) ERR#-93 'Protocol not 
supported'
36723: write(6,"@",1)             = 1 (0x1)
36723: close(6)                = 0 (0x0)
36723: close(5)                = 0 (0x0)
36723: linux_rt_sigaction(0x11,0xffffbaf8,0xffffba6c,0x8) = 0 (0x0)
36723: linux_exit_group(0x1)
36723: process exit, rval = 1

 My second current box ( r313090 i386 ) runs skype successfully.