AFP news agency quoted her uncle, Ben Semenya, as saying: "Caster is a girl... I am not worried about that too much. Caster is like my child. I know where she comes from. For myself, I know Caster is a girl."
The ex-wife of former President Nelson Mandela, Winnie Madikizela-Mandela, also greeted her.
"We are here to tell the whole world how proud we are of our little girl," the Associated Press quoted her as telling the cheering crowd of fans.
"They can write what they like - we are proud of her."
Our correspondent says Ms Semenya then sat silently through an hour-long news conference, looking mortified as various officials spoke in her defence.
Ms Semenya's family in Limpopo province has shown the BBC her birth certificate, which states she is female.
Athletics South Africa President Leonard Chuene last week told a local paper he had had to "persuade" the athlete to go to the podium to accept her gold medal because she was so upset about the gender row.
The ANC women's league said it viewed the order for the test by the International Association of Athletics Federations (IAAF) "as [a] vicious attack on the dignity of Caster Semenya and all women athletes because they suggest that women can only perform to a certain level and that those who exceed this level should be men".
IAAF President Lamine Diack accepted that the affair had been handled badly.
"I deeply regret that confidentiality was breached in this case and that the IAAF were forced into a position of having to confirm that gender testing was being carried out on this young athlete," AP quoted him as saying on Sunday.
"It is a regrettable matter and I have requested an internal inquiry to ensure that procedures are tightened up and this never happens again."
The IAAF ordered Ms Semenya to take the "gender verification test" after she improved her personal best by more than eight seconds over the past year.
The IAAF stresses that it does not suspect her of deliberately cheating, but questions whether she may have a rare medical condition which gives her an unfair advantage.
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