diff --git a/debian/patches/disable-relax4.patch b/debian/patches/disable-relax4.patch
new file mode 100644
index 0000000..765283d
--- /dev/null
+++ b/debian/patches/disable-relax4.patch
@@ -0,0 +1,21 @@
+Description: Disable Relax4 test
+ The corresponding routine in GLPK has been disabled, due to licensing issues.
+Author: Sébastien Villemot <sebastien@debian.org>
+Bug-Debian: https://bugs.debian.org/978311
+Forwarded: no
+Last-Update: 2021-01-14
+---
+This patch header follows DEP-3: http://dep.debian.net/deps/dep3/
+--- a/swig/Makefile.am
++++ b/swig/Makefile.am
+@@ -93,10 +93,6 @@ check:
+ 	  java -Djava.library.path=../../swig/.libs \
+ 	  -classpath ../../swig/glpk-java.jar:. MinimumCostFlow && \
+ 	  rm mincost.dimacs mincost.lp
+-	cd ../examples/java;$(JAVAC) -source 1.8 -target 1.8 \
+-	  -classpath ../../swig/glpk-java.jar Relax4.java
+-	cd ../examples/java;java -Djava.library.path=../../swig/.libs \
+-	  -classpath ../../swig/glpk-java.jar:. Relax4 sample.min
+ 
+ check-swing:
+ 	cd ../examples/java;$(JAVAC) -source 1.8 -target 1.8 \
diff --git a/debian/patches/series b/debian/patches/series
index 8b13789..6f00720 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -1 +1,2 @@
 
+disable-relax4.patch