diff --git a/Modules/regexpr.c b/Modules/regexpr.c
index 2d30171..663e1de 100644
--- a/Modules/regexpr.c
+++ b/Modules/regexpr.c
@@ -486,7 +486,13 @@
 		for (a = 'A'; a <= 'Z'; a++)
 			re_syntax_table[a] = Sword;
 		for (a = '0'; a <= '9'; a++)
-			re_syntax_table[a] = Sword | Sdigit;
+			re_syntax_table[a] = Sword | Sdigit | Shexdigit;
+		for (a = '0'; a <= '7'; a++)
+			re_syntax_table[a] |= Soctaldigit;
+		for (a = 'A'; a <= 'F'; a++)
+			re_syntax_table[a] |= Shexdigit;
+		for (a = 'a'; a <= 'f'; a++)
+			re_syntax_table[a] |= Shexdigit;
 		re_syntax_table['_'] = Sword;
 		for (a = 9; a <= 13; a++)
 			re_syntax_table[a] = Swhitespace;