Umbraco verson 4.7.1

I have one umbraco site that uses MySql Database. Problem is that it does not display correctly Nepalese characters.

For example I have this character " " it displays correctly in RichText Editor. After I published the content It shows ?????????????????????????????????????????????????????????????????????????????? in webpage. but it displays correctly in RichText Editor.

I also checked Tidy is set to Utf8.

<TidyEditorContent>True</TidyEditorContent>

<TidyCharEncoding>UTF8</TidyCharEncoding>

I have also another website that uses MSSQL Database. it works perfectly on that website. Problem is if i use MySql Database.

Here is XSLT

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE xsl:stylesheet [ <!ENTITY nbsp "&#x00A0;"> ]>
<xsl:stylesheet 
  version="1.0" 
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform" 
  xmlns:msxml="urn:schemas-microsoft-com:xslt"
  xmlns:umbraco.library="urn:umbraco.library" xmlns:Exslt.ExsltCommon="urn:Exslt.ExsltCommon" xmlns:Exslt.ExsltDatesAndTimes="urn:Exslt.ExsltDatesAndTimes" xmlns:Exslt.ExsltMath="urn:Exslt.ExsltMath" xmlns:Exslt.ExsltRegularExpressions="urn:Exslt.ExsltRegularExpressions" xmlns:Exslt.ExsltStrings="urn:Exslt.ExsltStrings" xmlns:Exslt.ExsltSets="urn:Exslt.ExsltSets" 
  exclude-result-prefixes="msxml umbraco.library Exslt.ExsltCommon Exslt.ExsltDatesAndTimes Exslt.ExsltMath Exslt.ExsltRegularExpressions Exslt.ExsltStrings Exslt.ExsltSets ">
<xsl:output method="xml" omit-xml-declaration="yes"/>
<xsl:param name="currentPage"/>
<xsl:template match="/">
<!-- start writing XSLT -->
 <div class="sub-content-wrapper">
   <div class="content_border"> 
     <h3>  <xsl:value-of select="$currentPage/contentTitle"/></h3> 
   </div>   
      <xsl:if test="string-length($currentPage/contentImage)&gt;1">
        <img src="{$currentPage/contentImage}" width="600px"/>
      </xsl:if>  
  <div>     
     <xsl:value-of select="$currentPage/contentBody" disable-output-escaping="yes"/>    
   </div>   
   </div>
</xsl:template>
</xsl:stylesheet>

Any suggestions?

thanks

Jivan