fnFindDuplicates = function(mSymbols, mResult) {
			var aUniqueSymbols = [];
			var sSymbol;
			for (var sKey in mSymbols) {
				sSymbol = mSymbols[sKey];
				if (aUniqueSymbols.indexOf(sSymbol) === -1) {
					aUniqueSymbols.push(sSymbol);
				} else if (sSymbol !== undefined) {
					// Duplicated symbol found
					mResult[sSymbol] = true;
					Log.error("Symbol '" + sSymbol + "' is defined multiple times in custom currencies.", undefined, "NumberFormat");
				}
			}
		}
Compiles a map <code>this.mKnownCurrencySymbols</code>
of all custom currency symbols. Symbols are either defined in
the custom currency object itself, or are looked up on the
LocaleData in case an ISO Code is given.

It also checks if there are duplicated symbols defined,
which lead to an ambiguous parse result.

In case there are custom currencies defined on instance level,
it also compiles a map <code>this.mKnownCurrencyCodes</code>
of custom currency codes.

The function is only used by the Currency formatting.
@private