Strange IRQ number

I see some strange IRQ number for my em0 card on BETA4:
root_at_cassini:~# vmstat -i                                                                                                                                                    
interrupt                          total       rate
irq1: atkbd0                           6          0
irq6: fdc0                             1          0
irq14: ata0                       184947         16
irq15: ata1                       184946         16
cpu0: timer                     22110598       1999
irq256: em0                      6945039        628
^^^^^^^^^^^^^^^^
cpu1: timer                     22110396       1999
Total                           51535933       4661

On 6.2 it was shared with uhci. Now all uhci controllers gone from the 
vmstat but not from the system:

root_at_cassini:~# usbdevs                                                                                                                                                      
addr 1: UHCI root hub, Intel
addr 1: UHCI root hub, Intel
addr 1: UHCI root hub, Intel
addr 1: UHCI root hub, Intel
addr 1: EHCI root hub, Intel

root_at_cassini:~# dmesg | grep em0                                                                                                                                             
em0: <Intel(R) PRO/1000 Network Connection Version - 6.7.3> port 
0x4000-0x401f mem 0xd0100000-0xd011ffff irq 16 at device 0.0 on pci6
em0: Using MSI interrupt
em0: Ethernet address: 00:30:48:91:c0:90
em0: [FILTER]

The entire system work ok.

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- Best regards, Nikolay Pavlov. <<<-----------------------------------    
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