Hi,
You can match an ACL or a prefix-list under a route-map but you can not included the prefix-list command itself.
See the outputs from the CLI below:
R6(config)#route-map external
R6(config-route-map)#?
Route Map configuration commands:
continue Continue on a different entry within the route-map
default Set a command to its defaults
description Route-map comment
exit Exit from route-map configuration mode
help Description of the interactive help system
match Match values from routing table
no Negate a command or set its defaults
set Set values in destination routing protocol
R6(config-route-map)#match ip address ?
<1-199> IP access-list number
<1300-2699> IP access-list number (expanded range)
WORD IP access-list name
prefix-list Match entries of prefix-lists
R6(config-route-map)#match ip address pre
R6(config-route-map)#match ip address prefix-list ?
WORD IP prefix-list name
match ip address
http://www.cisco.com/en/US/docs/ios/12_3/iproute/command/reference/ip2_k1g.html#wp1058320
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When you redistribute any protocol into OSPF if you do not specify the metric, the default cost of 1 is applied for BGP and 20 for all other protocols. Changing the metirc or tagging any specific routes while redistributing depends on the requirements and is not mandatory.
http://www.ciscopress.com/articles/article.asp?p=27573
HTH,
~Vaibhav