Error "System.ArgumentNullException: Key cannot be null" when i add twice same project item

Hi,

I have an error in my package.

I add a solution I add an project : ok
I add an item project (ex BizComponents): ok
When i add the same item project (BizComponents), so i get this error

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System.ArgumentNullException: Key cannot be null.
Parameter name: key
at System.Collections.Hashtable.get_Item(Object key)
at Microsoft.Practices.WizardFramework.WizardGatheringService.GetWizardConfiguration(XmlElement data)
at Microsoft.Practices.WizardFramework.WizardGatheringService.Microsoft.Practices.Common.Services.IValueGatheringService.Execute(XmlElement data, Boolean allowSuspend)
at Microsoft.Practices.RecipeFramework.VisualStudio.Templates.TemplateGatheringService.Microsoft.Practices.Common.Services.IValueGatheringService.Execute(XmlElement serviceData, Boolean allowSuspend)
at Microsoft.Practices.RecipeFramework.Recipe.Execute(Boolean allowSuspend)
at Microsoft.Practices.RecipeFramework.GuidancePackage.Execute(String recipe, IAssetReference reference, IDictionary arguments)
at Microsoft.Practices.RecipeFramework.GuidancePackage.Execute(String recipe, IDictionary arguments)
at Microsoft.Practices.RecipeFramework.VisualStudio.Templates.UnfoldTemplate.ExecuteRecipe(Boolean executeActions)
at Microsoft.Practices.RecipeFramework.VisualStudio.Templates.UnfoldTemplate.RunStarted(Object automationObject, Dictionary`2 replacementsDictionary, WizardRunKind runKind, Object[] customParams)

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this is my vstemplate :

<VSTemplate Version="2.0.0" Type="Item" xmlns="http://schemas.microsoft.com/developer/vstemplate/2005">

<TemplateData>

<Name>Empty Class Business components</Name>

<Description>A class receiving arguments for dynamic code generation</Description>

<Icon Package="{FAE04EC1-301F-11d3-BF4B-00C04F79EFBC}" ID="4515" />

<ProjectType>CSharp</ProjectType>

<SortOrder>10</SortOrder>

<DefaultName>Class.cs</DefaultName>

</TemplateData>

<TemplateContent>

<References>

<Reference>

<Assembly>System</Assembly>

</Reference>

<Reference>

<Assembly>System.Data</Assembly>

</Reference>

<Reference>

<Assembly>System.Xml</Assembly>

</Reference>

<Reference>

<Assembly>BICoreLib</Assembly>

</Reference>

<Reference>

<Assembly>mscorlib</Assembly>

</Reference>

</References>

<ProjectItem SubType="Code" TargetFileName="$fileinputname$.cs" ReplaceParameters="true">ClassBusinessComponents.cs</ProjectItem>

</TemplateContent>

<WizardExtension>

<Assembly>Microsoft.Practices.RecipeFramework.VisualStudio, Version=1.0.51206.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a</Assembly>

<FullClassName>Microsoft.Practices.RecipeFramework.VisualStudio.Templates.UnfoldTemplate</FullClassName>

</WizardExtension>

<WizardData>

<Template xmlns="http://schemas.microsoft.com/pag/gax-template"

SchemaVersion="1.0"

Recipe="NewItemClassBusinessComponents">

<References>

</References>

</Template>

</WizardData>

</VSTemplate>

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and my Recipe