Nigerian-born sprinter Ambrose Ezenwa has been cleared to run for Australia at the Games.
Irish distance runner Sonia O'Sullivan has been given the go-ahead to compete for Australia at the Games.
The 36-year-old, who has been granted dual citizenship, would normally have to wait three years to compete for another country.
However, organisers have accepted that the Commonwealth Games are not covered by the rule, although the loophole will be closed after the Melbourne event.
The Commonwealth Games Federation (CGF) announced its decision after consultation with Athletics Australia and the International Association of Athletic Federations.
Nigerian sprinter Ambrose Ezenwa, who was also affected by the ruling, can now legally compete for the host nation.
The Chief Executive Officer of the CGF, Mike Hooper, explained that IAAF rule 524, which prevents athletes with dual citizenships competing at other international sporting events, will come into effect after the Melbourne 2006 Commonwealth Games has finished.
"The change will take place immediately after the Closing Ceremony," Mr Hooper said.
"In the future we are 100 percent committed to delivering what is expected from a high level competition."
- Games News Service
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