[TYPO3-mvc] Translate f:uri.resource from "EXT:tx_ext..." to correct path?

[Jan Kornblum]

Dear newsgroup,

in a backend module i would like to embed javascript using 
<f:be.container>:

<f:be.container
	addJsFile="{f:uri.resource(path: '{settings.tx_ext_js}')}">
</f:be.container>

...where "settings.tx_ext_js" contains the string 
"EXT:my_ext/Resources/Public/Js/script.js".

How can i "translate" the "EXT:my_ext..." notation to a correct path?

Kind regards, Jan