error creating section handler

[helpful sql]

Hi all,
I am getting an exception from asp.net application that says error
creating section handler.
Here is my configuration section from web.config file:

<configSections>
<section name="ProposalTemplateNameSpaces"
type="System.Configuration.NameValueSectionHandler " />
</configSections>

<ProposalTemplateNameSpaces>
<add key="w" value="http://schemas.microsoft.com/office/word/2003/wordml"
/>
<add key="ns0" value="http://tempuri.org/datasetMPI.xsd" />
</ProposalTemplateNameSpaces>

The exception shows the second line - <section> tag in red. Any idea on what
I may be doing wrong here?

Thanks.