Format of kernel entry jump table for DR DOS 5.0-6.0:
Offset	Size	Description	)
 00h  5 BYTEs	far jump to kernel entry point for CP/M CALL 5
 05h  5 BYTEs	far jump to kernel entry point for INT 20
 0Ah  5 BYTEs	far jump to kernel entry point for INT 21
 0Fh  5 BYTEs	far jump to kernel entry point for INT 22 (RETF)
 14h  5 BYTEs	far jump to kernel entry point for INT 23 (RETF)
 19h  5 BYTEs	far jump to kernel entry point for INT 24
 1Eh  5 BYTEs	far jump to kernel entry point for INT 25
 23h  5 BYTEs	far jump to kernel entry point for INT 26
 28h  5 BYTEs	far jump to kernel entry point for INT 27
 2Dh  5 BYTEs	far jump to kernel entry point for INT 28
 32h  5 BYTEs	far jump to kernel entry point for INT 2A (IRET)
 37h  5 BYTEs	far jump to kernel entry point for INT 2B (IRET)
 3Ch  5 BYTEs	far jump to kernel entry point for INT 2C (IRET)
 41h  5 BYTEs	far jump to kernel entry point for INT 2D (IRET)
 46h  5 BYTEs	far jump to kernel entry point for INT 2E (IRET)
 4Bh  5 BYTEs	far jump to kernel entry point for INT 2F
Notes:	all of these entry points are indirected through this jump table
	  to allow the kernel to be relocated into high memory while leaving
	  the actual entry addresses in low memory for maximum compatibility
	some of these entry points (22h,23h,24h,2Eh,2Fh) are replaced as soon
	  as COMMAND.COM is loaded, and return immediately to the caller, some
	  returning an error code (the original handler for INT 2F returns
	  AL=03h [fail]).