diff --git a/haiku-apps/beam/patches/beam-1.2.patchset b/haiku-apps/beam/patches/beam-1.2.patchset
index 01d96dc0e..c9ad23123 100644
--- a/haiku-apps/beam/patches/beam-1.2.patchset
+++ b/haiku-apps/beam/patches/beam-1.2.patchset
@@ -1,4 +1,4 @@
-From 3d9e9848cb33b00b285a089c549dd824a8839cff Mon Sep 17 00:00:00 2001
+From 8ac6320697a640db0be6e8cda9f69eb20e515e65 Mon Sep 17 00:00:00 2001
 From: Adrien Destugues <pulkomandy@pulkomandy.tk>
 Date: Sun, 8 Oct 2017 10:16:27 +0200
 Subject: Fix crash
@@ -22,3 +22,28 @@ index 490d5f9..4aa6d23 100644
 -- 
 2.14.2
 
+
+From 07bc84afb7f18dc3e91215d11fb6fc2bbabe24e2 Mon Sep 17 00:00:00 2001
+From: Adrien Destugues <pulkomandy@pulkomandy.tk>
+Date: Sun, 8 Oct 2017 11:25:09 +0200
+Subject: Fix build with current flex
+
+It is confused if we are C89 but define INT32_MAX anyway. So pretend we
+are C99.
+
+diff --git a/src-filter-addons/src-sieve/src-libSieve/Jamfile b/src-filter-addons/src-sieve/src-libSieve/Jamfile
+index cbe5db4..884d007 100644
+--- a/src-filter-addons/src-sieve/src-libSieve/Jamfile
++++ b/src-filter-addons/src-sieve/src-libSieve/Jamfile
+@@ -11,6 +11,8 @@ if $(OSPLAT) = X86 {
+ 	CCFLAGS += -proto lax -w nounwanted -w nounused ;
+ }
+ 
++CFLAGS += --std=gnu9x ;
++
+ SubDirSysHdrs $(COMMON_FOLDER)/include ;
+ 
+ # <pe-src>
+-- 
+2.14.2
+