Aspell dictionaries should be named LANGUAGE[_REGION][-VARIETY][-SIZE],
therefore this patch adds de-1901 and de_DE-1901 as such alias names.
See also: http://www.iana.org/assignments/language-subtag-registry

--- a/Makefile.pre
+++ b/Makefile.pre
@@ -7,7 +7,8 @@
 data_files = de-alt.dat de-alt_phonet.dat de-alt_affix.dat
 doc_files = README COPYING Copyright
 extra_files = configure info Makefile.pre
-multi_files = de-alt.multi deutsch-alt.alias german-old.alias
+multi_files = de-alt.multi deutsch-alt.alias german-old.alias \
+	de-1901.alias de_DE-1901.alias
 rws_files = de-alt.rws
 
 distdir=aspell6-${lang}-${version}
--- a/README
+++ b/README
@@ -1,4 +1,4 @@
-GNU Aspell 0.60 German - Old Spelling (Deutsch - Alter Spelling) Dictionary Package
+GNU Aspell 0.60 German - Old Spelling (Deutsch - alte Rechtschreibung) Dictionary Package
 Version 2.1-1
 2004-11-03
 Original Word List By:
@@ -46,7 +46,7 @@
 with "--lang=de-alt".  You may also chose the dictionary directly
 with the "-d" or "--master" option of Aspell.  You can chose from any of
 the following dictionaries:
-  de-alt (deutsch-alt german-old)
+  de-alt (deutsch-alt german-old de-1901 de_DE-1901)
 Whereas the names in parentheses are alternate names for the
 dictionary preceding the parentheses.
 
--- a/de-1901.alias
+++ b/de-1901.alias
@@ -0,0 +1 @@
+add de-alt.multi
--- a/de_DE-1901.alias
+++ b/de_DE-1901.alias
@@ -0,0 +1 @@
+add de-alt.multi
--- a/info
+++ b/info
@@ -1,5 +1,5 @@
 name_english German - Old Spelling
-name_ascii Deutsch - Alter Spelling
+name_ascii Deutsch - alte Rechtschreibung
 lang de-alt
 data-file de-alt_phonet.dat
 data-file de-alt_affix.dat
@@ -13,7 +13,7 @@
 version 2.1-1
 accurate true
 complete true
-alias de-alt german-old deutsch-alt
+alias de-alt german-old deutsch-alt de-1901 de_DE-1901
 dict:
   name de-alt
   add de-alt