Is this habeas corpus and what can I do about this?

Of course the situation you describe is not the habeas corpus as such. Your friend might be helped by eight ridge of habeas corpus. But there are faster ways to get him out. He should retain a skilled family law attorney, and have him or her notify both the judge and also who ever issued the warrant, that you are free and is in jail illegally. It is likely that he will be released promptly. But a lawyer is generally more effective. Good luck.