Windows 98 / MS-DOS Software Interrupt

[brightblade81]

I've using Virtualbox 4.1.4, host OS: Fedora 15, Guest OS: Windows 98 with a processor that supports VT-X

Question:
How do I enable Software Interrupts for Windows 98 through VirtualBox?

Background:
Some software I have to run in Windows 98 uses a TSR Program(from the MS-DOS days) and that uses a Software Interrupt but when I run it, it reports NO available software interrupts were found when it tries to register one. It appears to be a problem with VirtualBox not making any available for Windows 98/Ms-Dos as VMWare's player works fine when the same setup and software is run, QEMU/KVM randomly crashes when trying to install Windows 98. I'm using VirtualBox for the PCI-passthrough which is working fine.