Casio keyboard

[Daij]

I have a Casio CT-360 keyboard and I want to play it through a Marshall guitar amplifier. The output socket is very small - will take a small PC/mobile phone headphone jack. I need a lead with a standard guitar jack on one end and a small jack on the other. Even though the socket on my keyboard will take the headphone jack plug, the headphones do not work when I plug it.
Anyone have any idea what a suitable jack would be called so I can buy the correct one. I guess I'll have to make a lead up with this configuration - I've never seen one for sale 'over the counter'.

Thanks in advance

[TheWinner]

Can't you get a lead made up at your local guitar shop? Just tell them what you want, I have had these made up before. You can't buy them over the counter, you have to ask for them to be made up. It doesn't have a specific name.

[rojash]

Or, if you already have a 3.5mm - 3.5mm jack lead, you could just buy an adaptor:
http://tinyurl.com/42crn8p
(Though TheWinner will probably tell you that they don't exist either)

[Daij]

Thanks to you all