diff --git a/doc/checksums.txt b/doc/checksums.txt
index a9fa482..9710584 100644
--- a/doc/checksums.txt
+++ b/doc/checksums.txt
@@ -290,7 +290,7 @@ described here. This feature allows scdbackup to omit its own checksum filter
 if using xorriso as ISO 9660 formatter program.
 Such a tag makes only sense if the session begins at LBA 0.
 
-See scdbackup-*/README, appendix VERIFY for a specification
+See scdbackup-*/README, appendix VERIFY for a specification.
 
 Example of a scdbackup checksum tag:
 scdbackup_checksum_tag_v0.1 2456606865 61 2_2 B00109.143415 2456606865 485bbef110870c45754d7adcc844a72c c2355d5ea3c94d792ff5893dfe0d6d7b
diff --git a/libisofs/aaip-os-freebsd.c b/libisofs/aaip-os-freebsd.c
index 8d00103..dc24bc5 100644
--- a/libisofs/aaip-os-freebsd.c
+++ b/libisofs/aaip-os-freebsd.c
@@ -18,6 +18,7 @@
 #include <string.h>
 #include <stdio.h>
 #include <sys/stat.h>
+#include <errno.h>
 
 #ifndef Libisofs_with_aaip_acL
 /* It seems ACL is fixely integrated in FreeBSD libc. There is no libacl. */
@@ -37,13 +38,14 @@
                         finally has to be freed by a call to this function
                         with bit15 of flag.
    @param flag          Bitfield for control purposes
-                        bit0=  obtain default ACL rather than access ACL
+                        (bit0=  obtain default ACL rather than access ACL)
                         bit4=  set *text = NULL and return 2
                                if the ACL matches st_mode permissions.
                         bit5=  in case of symbolic link: inquire link target
                         bit15= free text and return 1
    @return              > 0 ok
                           0 ACL support not enabled at compile time
+                            or filesystem does not support ACL
                          -1 failure of system ACL service (see errno)
                          -2 attempt to inquire ACL of a symbolic
                             link without bit4 or bit5
@@ -88,8 +90,18 @@ int aaip_get_acl_text(char *path, char **text, int flag)
 
  acl= acl_get_file(path, ACL_TYPE_ACCESS);
 
- if(acl == NULL)
+ if(acl == NULL) {
+   if(errno == EOPNOTSUPP) {
+     /* filesystem does not support ACL */
+     if(flag & 16)
+       return(2);
+
+     /* >>> ??? fake ACL from POSIX permissions ? */;
+
+     return(0);
+   }
    return(-1);
+ }
  *text= acl_to_text(acl, NULL);
  acl_free(acl);
 
@@ -181,10 +193,8 @@ int aaip_get_attr_list(char *path, size_t *num_attrs, char ***names,
 
  if(flag & 1) { /* Obtain ACL */
    /* access-ACL */
-   ret= aaip_get_acl_text(path, &acl_text, flag & (16 | 32));
-   if(ret <= 0)
-     goto ex;
-   if(ret == 2)
+   aaip_get_acl_text(path, &acl_text, flag & (16 | 32));
+   if(acl_text == NULL)
      {ret= 1; goto ex;} /* empty ACL / only st_mode info was found in ACL */
    ret= aaip_encode_acl(acl_text, (mode_t) 0, &a_acl_len, &a_acl, flag & 2);
    if(ret <= 0)
diff --git a/libisofs/aaip-os-linux.c b/libisofs/aaip-os-linux.c
index ba8a06e..c8a208c 100644
--- a/libisofs/aaip-os-linux.c
+++ b/libisofs/aaip-os-linux.c
@@ -18,6 +18,8 @@
 #include <string.h>
 #include <stdio.h>
 #include <sys/stat.h>
+#include <errno.h>
+
 
 #ifdef Libisofs_with_aaip_acL
 #include <sys/acl.h>
@@ -46,6 +48,7 @@
                           2 only st_mode permissions exist and bit 4 is set
                             or empty ACL and bit0 is set
                           0 ACL support not enabled at compile time
+                            or filesystem does not support ACL
                          -1 failure of system ACL service (see errno)
                          -2 attempt to inquire ACL of a symbolic link without
                             bit4 or bit5 resp. with no suitable link target
@@ -79,8 +82,18 @@ int aaip_get_acl_text(char *path, char **text, int flag)
  }
  
  acl= acl_get_file(path, (flag & 1) ? ACL_TYPE_DEFAULT : ACL_TYPE_ACCESS);
- if(acl == NULL)
+ if(acl == NULL) {
+   if(errno == ENOTSUP) {
+     /* filesystem does not support ACL */
+     if(flag & 16)
+       return(2);
+   
+     /* >>> ??? fake ACL from POSIX permissions ? */;
+
+     return(0);   
+   }
    return(-1);
+ }
  *text= acl_to_text(acl, NULL);
  acl_free(acl);
 
diff --git a/libisofs/libisofs.h b/libisofs/libisofs.h
index 99dd1ae..96e4436 100644
--- a/libisofs/libisofs.h
+++ b/libisofs/libisofs.h
@@ -4566,7 +4566,7 @@ int iso_node_set_attrs(IsoNode *node, size_t num_attrs, char **names,
  * @return
  *        1 ok 
  *        2 ok, trivial ACL found while bit4 is set, *text is NULL 
- *        0 no ACL manipulation adapter available
+ *        0 no ACL manipulation adapter available / ACL not supported on fs
  *       -1 failure of system ACL service (see errno)
  *       -2 attempt to inquire ACL of a symbolic link without bit4 or bit5
  *          resp. with no suitable link target