Well you could try something like this, where check() is simply your function which is called everytime your going to check for players, whether it be in PreThink or a task you set every second or so:
PHP Code:
public check( id )
{
new num, list[ 32 ], Float:dist = 1000.0;
num = find_sphere_class( id, "player", dist, list, 32 );
new player;
for ( new i ; i < num ; i++ )
{
player = list[ i ];
if( !is_user_alive( player ) || get_user_team( player ) != get_user_team( id ) )
continue;
//unfreeze player
}
}
EDIT: Can only players only unfreeze a team mate?