large memory not accessible

After the memory was increased to 8 Gb from 2 Gb on a ubuntu 10.04 system the Fortran compiler will not compile a code that uses more than 2 GB of array storage, the error message is:
/opt/intel/Compiler/11.1/072/lib/intel64/libifcore.a(for_init.o): In function `for__signal_handler':
for_init.c:(.text+0xf1): relocation truncated to fit: R_X86_64_PC32 against `for__protect_handler_ops'

A second compiler will compile a code using 3.5 GB of array storage but fails with 4. GB. The error message is very similar. The bios reports 8 GB upon boot up. The swap space is only 4.9 Gb. Is this the problem? How can the swap space be increased without reinstalling ubuntu?