Weird but I can't find where is € symbol set in Magento 1.3.2.3. My locale is German, so I checked /lib/Zend/Locale/Data/de.xml, but for Euro it only have the following code:
<currency type="EUR">
<displayName>Euro</displayName>
<displayName count="other">Euro</displayName>
</currency>
However at the front-end the € symbol is displayed. Please help.
Take a look into lib/Zend/Locale/Data/characters.xml There you'll find wich characters are used to replace the definitions.
For example:
<currency type="EUR">
Type EUR will be replaced for the € symbol.