This looks like it will do the job and loads more.
It will even acts as a stand-alone midi merge box (great for merging a c/controller device & midi keyboard to the emu)
so not too much of a risk to try with your system at this price, even with the small chance of incompatability it is a steal.
and very cheap too £22.95 delivered
EBAY link
http://cgi.ebay.co.uk/Midi-4i4o-Merge-2i4o-USB-4-4-64-Channels-Converters-/360277043619?pt=UK_Computing_CablesConnectors_RL&hash=item53e22f69a3 Midi 4i4o + Merge 2i4o USB 4× 4 64 Channels Converters
The MIDI USB 4i4o is a convenient 4 in / 4 out, 64 channels, USB MIDI interface for PC and Mac computers. With the MIDI USB 4i4o you can obtain perfect MIDI timing and performance at extremely affordable price.
Features:
1. 4 MIDI inputs and 4 MIDI outputs (64 MIDI channels)
2. Merge function 2 ins-> 4 outs included
3. Perfect MIDI timing
4. High-speed connection to USB-equipped PC or Macintosh computers
5. USB-powered, required no external power supply
6. Compact size, light weight, easy to carry
7. Compatible with Windows XP, Vista, 7 and Mac OSX or better
8. Plug and play, do not need to install driver
Description:
Color: Black
Material: Metal
Midi 4i4o + Merge 2i4o
1 * USB 2.0 interface, 8 * MIDI interfaces
Compatible with Windows XP, Vista, 7 and Mac OSX or better
Dimension: 145*84*40mm
USB Cable Length: 1.5M
Net weight: 345g
Package weight: 546g
Package size: 208*165*70mm