Protected \crossrefenum against early expansion.

It occured in ConTeXt in a \footnote with \setupinteraction[state=start].'

tex/crossrefenum.tex

@@ -524,13 +524,22 @@
 
 %%% \crossrefenum: Public macro with optional arguments %%%
 
+\crfnm@case[\fmtname]
+  \crfnm@context: {
+    \unexpanded\def\crossrefenum{\crfnm@crossrefenum}
+  }
+  \crfnm@latex: {
+    \protected\def\crossrefenum{\crfnm@crossrefenum}
+  }
+\crfnm@endCases
+
 % \crossrefenum has two optional arguments.
 % See the definition of \crfnm@enum below for the recognized values.
 
 \def\crfnm@firstArg@default{page}
 \def\crfnm@secondArg@default{withprefix}
 
-\def\crossrefenum{%
+\def\crfnm@crossrefenum{%
   \futurelet\crfnm@nextToken\crfnm@setEnumMacro
 }