ampersand in Parameter password item

Hi
In my Project Build Configuration, I created a Parameter: p_pwd as a password field, and the password value that gets saved contains an ampersand - &  
Example value:    one-Two&three

When the build step that uses the paramter %p_pwd% executes it, the build fails with:
'three' is not recognized as an internal or external command

The build step is:
Runner Type: Command Line
Run: Custom Script
Custom Script: echo Y | plink -agent -pw %p_pwd% user1@server1; pwd

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The Script works if the password does not contain an ampersand, is there a way to escape the ampersand in the password parameter?


Thanks,
Coenraad