Here, try this:
package tumble
{
function servercmdTumble(%client, %user)
{
if(%client.isSuperAdmin == false || %client.isAdmin == false)
{
return;
}
if(%user !$= "")
{
%target = findClientByName(%user).player;
%targetC = findClientByName(%user);
%target.tumble();
messageClient(%client, '', '\c5%1 is now tumbling!', %targetC.name);
messageClient(%targetC, '', '\c6You are now tumbling!', %user);
} else {
%client.player.tumble();
messageClient(%client, '', '\c6You are now tumbling!', %user);
}
}
};
ActivatePackage(tumble);