var pressed='';

function hover(this_button)
{
if(!document.images){return;}
if(this_button==''){return;}
if(this_button==pressed){return;}
document.images[this_button].src='/buttons/'+this_button+'_h.png';
}

function normal(this_button)
{
if(!document.images){return;}
if(this_button==''){return;}
if(this_button==pressed){return;}
document.images[this_button].src='/buttons/'+this_button+'_n.png';
}

function press(this_button)
{
if(pressed==this_button){return;}
if(!document.images){return;}
if(pressed != '')
{
if(!document.images[pressed]){alert("zu deselektierenden Button '"+pressed+"' nicht gefunden!");}
else{document.images[pressed].src='/buttons/'+pressed+'_n.png';}
}

if(this_button!=''){document.images[this_button].src='/buttons/'+this_button+'_s.png';pressed=this_button;}
}

function press_topmenu_button(this_button)
{if(top.frames['mainMenu']){top.frames['mainMenu'].press(this_button);}}