Abort in HP-UX 11.0. parameters limiting the size of program

[cislago]

Problem that i am facing - A Unix System aborts during the execution of a program stating:
PROGRAM ABORTED: HEAP allocation request FAILED (Unwind 31)

Workstation: HP B180L, 128 Mb RAM, 9 Gb HD.
Operating System: HP-UX 11.0
Compilers Used: Fortran77 & C
Drafting driver: Starbase
Rest is developed by ourselves i.e. Fully under our control

BDF Status during execution
Filesystem kbytes used %used
/ 144000 88700 63%
/stand 84000 25000 33%
/var 512000 368000 73%
/usr 512000 386000 76%
/temp 65000 1300 2%
/opt 820000 799000 98%
/home 4910000 794000 17%

Executable file length - 1.07 Mb
Maximum RAM required by the test - 4.20 Mb
Print Files at the moment of Abort - 1.50 kb

The abort during the execution of this partial test worries me if have to keep in account other limitations during the assembly of an "application system" which in the final stage may reach a volume 10 times this partial test.

Further what strategy we have to adopt in porting the application to Linux?

Thanks in application for the help I get to overcom the problem and for all valuable suggestions.