How to create a using the struts.properties file

[Struts2 Fan]

Hi I want to use the <s:select> using the struts.properties file

struts.properties file
country.values = Italy,Holland
country.keys = 1,2

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<s:select listKey="country.keys" listValue="country.values">

but <s:select> requires list attribute. How can I solve this problem?

Thanks...