diff -Naupr zziplib-0.13.49.orig/zzip/_config.h zziplib-0.13.49/zzip/_config.h
--- zziplib-0.13.49.orig/zzip/_config.h	2007-03-18 12:59:51.000000000 +0100
+++ zziplib-0.13.49/zzip/_config.h	2008-12-22 10:02:32.351372027 +0100
@@ -130,9 +130,11 @@
 
 /* whether the system defaults to 32bit off_t but can do 64bit when requested
    */
+#if __WORDSIZE == 32
 #ifndef ZZIP_LARGEFILE_SENSITIVE 
 #define ZZIP_LARGEFILE_SENSITIVE  1 
 #endif
+#endif
 
 /* Name of package */
 #ifndef ZZIP_PACKAGE 
@@ -171,7 +173,11 @@
 
 /* The number of bytes in type long */
 #ifndef ZZIP_SIZEOF_LONG 
+#if __WORDSIZE == 32
 #define ZZIP_SIZEOF_LONG  4 
+#elif __WORDSIZE == 64
+#define ZZIP_SIZEOF_LONG  8 
+#endif
 #endif
 
 /* The number of bytes in type short */
@@ -194,9 +200,11 @@
 /* #undef WORDS_BIGENDIAN */
 
 /* Number of bits in a file offset, on hosts where this is settable. */
+#if __WORDSIZE == 32
 #ifndef ZZIP__FILE_OFFSET_BITS 
 #define ZZIP__FILE_OFFSET_BITS  64 
 #endif
+#endif
 
 /* Define for large files, on AIX-style hosts. */
 /* #undef _LARGE_FILES */