Well, right at the moment the ATMEL server is down, so I am unable to find the latest datasheet of AT89C2051 but the datasheet which I already have does not have any such information which you quoted.

On first page, some features of AT89C2051 are given. From them, the number 11 is

• Direct LED Drive Outputs

and at the end of DC Characteristics table,

Notes:
1. Under steady state (non-transient) conditions, I OL must be externally limited as follows:
.Maximum IOL per port pin: 20 mA
.Maximum total IOL for all output pins: 80 mA
.If IOL exceeds the test condition, V OL may exceed the related specification. Pins are not guaranteed to sink current greater
than the listed test conditions.

I could not find any information about IOH. But what you have quoted about IOH is not actually about the maximum value of IOH, rather it is mentioned to show the value of VOH at a load (IOH) of -80 uA.

The circuit shown by Charles utilizes IOL to lit the LED, which is 20mA(max) for a port pin.

May be I am mistaken, but can you please throw some light why the circuit suggested by Charles Bannister, will not work. I don't see any problem in it.

The datasheet revision number is Rev. 0368E–02/00

Regards
Ijaz