diff -urN proftpd-1.2.10/include/data.h proftpd-1.2.10-sendfile64/include/data.h
--- proftpd-1.2.10/include/data.h	2004-05-21 19:19:02.000000000 +0200
+++ proftpd-1.2.10-sendfile64/include/data.h	2005-02-03 17:18:39.676660624 +0100
@@ -36,25 +36,12 @@
 int pr_data_open(char *, char *, int, off_t);
 void pr_data_close(int);
 void pr_data_abort(int, int);
-int pr_data_xfer(char *, int);
+off_t pr_data_xfer(char *, int);
 void pr_data_reset(void);
 void pr_data_set_linger(long);
 
 #ifdef HAVE_SENDFILE
-typedef
-
-#if defined(HAVE_AIX_SENDFILE) || defined(HAVE_HPUX_SENDFILE) || \
-    defined(HAVE_LINUX_SENDFILE) || defined(HAVE_SOLARIS_SENDFILE)
-ssize_t
-#elif defined(HAVE_BSD_SENDFILE)
-off_t
-#else
-#error "You have an unknown sendfile implementation."
-#endif
-
-pr_sendfile_t;
-
-pr_sendfile_t pr_data_sendfile(int retr_fd, off_t *offset, size_t count);
+off_t pr_data_sendfile(int retr_fd, off_t *offset, off_t count);
 #endif /* HAVE_SENDFILE */
 
 #endif /* PR_DATACONN_H */
diff -urN proftpd-1.2.10/modules/mod_xfer.c proftpd-1.2.10-sendfile64/modules/mod_xfer.c
--- proftpd-1.2.10/modules/mod_xfer.c	2004-08-25 00:24:18.000000000 +0200
+++ proftpd-1.2.10-sendfile64/modules/mod_xfer.c	2005-02-03 17:18:26.109723112 +0100
@@ -603,7 +603,7 @@
   return;
 }
 
-static int _transmit_normal(char *buf, long bufsize) {
+static off_t _transmit_normal(char *buf, long bufsize) {
   long count;
 
   if ((count = pr_fsio_read(retr_fh, buf, bufsize)) <= 0)
@@ -614,7 +614,7 @@
 
 #ifdef HAVE_SENDFILE
 static int _transmit_sendfile(off_t count, off_t *offset,
-    pr_sendfile_t *retval) {
+    off_t *retval) {
 
   /* We don't use sendfile() if:
    * - We're using bandwidth throttling.
@@ -670,8 +670,8 @@
 }
 #endif /* HAVE_SENDFILE */
 
-static long _transmit_data(off_t count, off_t offset, char *buf, long bufsize) {
-  long res;
+static off_t _transmit_data(off_t count, off_t offset, char *buf, long bufsize) {
+  off_t res;
 
 #ifdef TCP_CORK
   int on = 1;
@@ -679,7 +679,7 @@
 #endif /* TCP_CORK */
 
 #ifdef HAVE_SENDFILE
-  pr_sendfile_t retval;
+  off_t retval;
 #endif /* HAVE_SENDFILE */
 
 #ifdef TCP_CORK
@@ -695,7 +695,7 @@
   if (!_transmit_sendfile(count, &offset, &retval))
     res = _transmit_normal(buf, bufsize);
   else
-    res = (long) retval;
+    res = retval;
 #else
   res = _transmit_normal(buf, bufsize);
 #endif /* HAVE_SENDFILE */
@@ -1526,8 +1526,8 @@
   off_t nbytes_max_retrieve = 0;
   unsigned char have_limit = FALSE;
   privdata_t *p;
-  long bufsize, len = 0;
-  off_t respos = 0, nbytes_sent = 0, cnt_steps = 0, cnt_next = 0;
+  long bufsize;
+  off_t respos = 0, nbytes_sent = 0, cnt_steps = 0, cnt_next = 0, len = 0;
 
   /* This function sets static module variables for later potential
    * throttling of the transfer.
diff -urN proftpd-1.2.10/src/data.c proftpd-1.2.10-sendfile64/src/data.c
--- proftpd-1.2.10/src/data.c	2004-08-25 20:08:46.000000000 +0200
+++ proftpd-1.2.10-sendfile64/src/data.c	2005-02-03 17:20:56.858805768 +0100
@@ -772,9 +772,9 @@
  * closes, or -1 if error
  */
 
-int pr_data_xfer(char *cl_buf, int cl_size) {
-  int len = 0;
-  int total = 0;
+off_t pr_data_xfer(char *cl_buf, int cl_size) {
+  off_t len = 0;
+  off_t total = 0;
 
   if (session.xfer.direction == PR_NETIO_IO_RD) {
     char *buf = session.xfer.buf;
@@ -910,9 +910,9 @@
  * ASCII translation is not performed.
  * return 0 if reading and data connection closes, or -1 if error
  */
-pr_sendfile_t pr_data_sendfile(int retr_fd, off_t *offset, size_t count) {
+off_t pr_data_sendfile(int retr_fd, off_t *offset, off_t count) {
   int flags, error;
-  pr_sendfile_t len = 0, total = 0;
+  off_t len = 0, total = 0;
 #if defined(HAVE_AIX_SENDFILE)
   struct sf_parms parms;
   int rc;
@@ -932,14 +932,19 @@
   for (;;) {
 #if defined(HAVE_LINUX_SENDFILE) || defined(HAVE_SOLARIS_SENDFILE)
     off_t orig_offset = *offset;
+    off_t translen = 0;
 
+    if (count > 1024*1024*1024)
+      translen = 1024*1024*1024;
+    else
+      translen = count;
     /* Linux semantics are fairly straightforward in a glibc 2.x world:
      *
      * #include <sys/sendfile.h>
      *
      * ssize_t sendfile(int out_fd, int in_fd, off_t *offset, size_t count)
      */
-    len = sendfile(PR_NETIO_FD(session.d->outstrm), retr_fd, offset, count);
+    len = sendfile(PR_NETIO_FD(session.d->outstrm), retr_fd, offset, (size_t)translen);
 
     if (len != -1 && len < count) {
       /* under linux semantics, this occurs when a signal has interrupted