No "encapsulation" command on IOS 12.2(12a) ??

Fri Oct 24 09:49:15 UTC 2003

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Cisco Internetwork Operating System Software
IOS (tm) 3600 Software (C3620-I-M), Version 12.2(12a), RELEASE SOFTWARE (fc1)

flash image:
System image file is "flash:c3620-i-mz.122-12a.bin"

I'm trying to configure a FastEthernet sub interface for 802.1q VLANs, but
theres no encapsulation command. I've googled it up for about 2 hours and
have come up with nothing... the following command sequence is documented
dozens of times:

As shown on:

http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/120newft/120t/120t1/8021q.htm#wp3944
interface fastethernet slot/port.subinterface-number
encapsulation dot1q vlanid

Any help would be appreciated.