V7.3.1 using the "Send to Translation" function is resulting in the following error showing in the translation slide-out in the Umbraco UI as soon as you hit the "OK" button:

    Server Error in '/' Application.

Object reference not set to an instance of an object.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. 

Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.

Source Error: 

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace: 


[NullReferenceException: Object reference not set to an instance of an object.]
   umbraco.cms.businesslogic.translation.Translation.MakeNew(CMSNode Node, User User, User Translator, Language Language, String Comment, Boolean IncludeSubpages, Boolean SendEmail) +49
   umbraco.presentation.dialogs.sendToTranslation.doTranslation_Click(Object sender, EventArgs e) +189
   System.Web.UI.WebControls.Button.OnClick(EventArgs e) +116
   System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +108
   System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +12
   System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +15
   System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +31
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +3582

Have tried with the Translator permissions set to just "Translation" and also to "Translation" and "Content" sections. Same error both times.

Anyone else seeing this?

Thanks,

Craig