The mkbootdisk script contains several typos. Here is a
patch:

--- mkbootdisk.orig     Thu Oct  8 14:50:25 1998
+++ mkbootdisk  Sun Nov  8 11:18:04 1998
@@ -34,7 +34,7 @@
            ;;
        --mkinitrdargs)
            shift
-           mkinitrdargs=#1
+           mkinitrdargs=$1
            ;;
        --help)
            usage 0
@@ -95,11 +95,11 @@
 [ -f /lib/modules/$kernel/fs/isofs.o ] &&
        withfs="$withfs --with isofs"
 [ -f /lib/modules/$kernel/fs/nfs.o ] &&
-       withfs="$withfs --with isofs"
+       withfs="$withfs --with nfs"
 [ -f /lib/modules/$kernel/fs/fat.o ] &&
-       withfs="$withfs --with isofs"
+       withfs="$withfs --with fat"
 [ -f /lib/modules/$kernel/fs/msdos.o ] &&
-       withfs="$withfs --with isofs"
+       withfs="$withfs --with msdos"