diff --git a/ChangeLog b/ChangeLog
index dca0d0b5..ddb0d85b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,6 @@
+17/4/12 started 7.28.4
+- up max buffer size for vipsbuf
+
 6/4/12 started 7.28.3
 - vips_divide() failed for int arguments
 - fix warning for unused vips7 gvalue argument
diff --git a/configure.in b/configure.in
index ee2def22..d29a1425 100644
--- a/configure.in
+++ b/configure.in
@@ -2,7 +2,7 @@
 
 # also update the version number in the m4 macros below
 
-AC_INIT(vips, 7.28.3, vipsip@jiscmail.ac.uk)
+AC_INIT(vips, 7.28.4, vipsip@jiscmail.ac.uk)
 # required for gobject-introspection
 AC_PREREQ(2.62)
 
@@ -15,7 +15,7 @@ AC_CONFIG_MACRO_DIR([m4])
 # user-visible library versioning
 m4_define([vips_major_version], [7])
 m4_define([vips_minor_version], [28])
-m4_define([vips_micro_version], [3])
+m4_define([vips_micro_version], [4])
 m4_define([vips_version],
           [vips_major_version.vips_minor_version.vips_micro_version])
 
@@ -35,7 +35,7 @@ VIPS_VERSION_STRING=$VIPS_VERSION-`date`
 #   interface changes not backwards compatible?: reset age to 0
 
 LIBRARY_CURRENT=31
-LIBRARY_REVISION=3
+LIBRARY_REVISION=4
 LIBRARY_AGE=16
 
 # patched into include/vips/version.h
diff --git a/libvips/iofuncs/buf.c b/libvips/iofuncs/buf.c
index 815fb76c..ea875ba2 100644
--- a/libvips/iofuncs/buf.c
+++ b/libvips/iofuncs/buf.c
@@ -74,7 +74,7 @@
 
 /* Largest string we can append in one operation.
  */
-#define MAX_STRSIZE (16000)
+#define MAX_STRSIZE (100000)
 
 /** 
  * VIPS_BUF_STATIC:
diff --git a/libvips/iofuncs/util.c b/libvips/iofuncs/util.c
index 882530e9..bf23160a 100644
--- a/libvips/iofuncs/util.c
+++ b/libvips/iofuncs/util.c
@@ -89,7 +89,7 @@
 
 /* Temp buffer for snprintf() layer on old systems.
  */
-#define MAX_BUF (32768)
+#define MAX_BUF (100000)
 
 /* Test two lists for eqality.
  */