-\def\descref@i#1#2#3#4{\@ifnextchar[%
- {\descref@ii{#1}{#2}{#3}{#4}}%
- {\descref@iii{#1}{#2}{#3}{#4}{}}}
-\def\descref@ii#1#2#3#4[#5]{\descref@iii{#1}{#2}{#3}{#4}{ #5}}
+\def\descref@i#1#2#3#4#5{\@ifnextchar@preserve[%
+ {\descref@ii{#1}{#2}{#3}{#4}{#5}}%
+ {\descref@iii{#1}{#2}{#3}{#4}{#5}{}}}
+\def\descref@ii#1#2#3#4#5[#6]{\descref@iii{#1}{#2}{#3}{#4}{#5}{ #6}}