Stored Procedure Error - No more data available to read.

I just started using stored procedure with Cold Fusion. Sometimes, I get this error..
Error Executing Database Query.  
[Macromedia][SQLServer JDBC Driver]No more data available to read.

If I refresh the page, sometimes it will show the data, other times I get the error. What's causing this?

<cfstoredproc procedure="Display_Products" datasource="#request.datasource#" username="#request.username#" password="#request.password#">
<cfprocparam cfsqltype="cf_sql_integer" value="#category#">
<cfprocresult name="spProducts">
</cfstoredproc>

<table cellpadding="2" cellspacing="2" align="center">
<tr>
<cfoutput query="spProducts" startrow="#Variables.StartRow#" maxrows="#Variables.RecordsPerPage#">
<td valign="top">
<div align="center" class="buttions"> Click image for larger view<br>
<a href="/#categoryid#/#image#"><img src = "/#categoryid#/thumbnails/#image#" border="0"></a><br>
#product#<br>
<strong>#DollarFormat(price)#</strong></font></div>
<br><br>
</td>
<cfif spProducts.CurrentRow MOD 4 IS 0>
</tr>
<tr>
</cfif>
</cfoutput>
</tr>
</table>