--- java/org/apache/jasper/compiler/JDTCompiler.java
+++ java/org/apache/jasper/compiler/JDTCompiler.java
@@ -302,9 +302,9 @@
             } else if (opt.equals("17")) {
                 settings.put(CompilerOptions.OPTION_Source, CompilerOptions.VERSION_17);
             } else if (opt.equals("18")) {
-                settings.put(CompilerOptions.OPTION_Source, CompilerOptions.VERSION_18);
+                settings.put(CompilerOptions.OPTION_Source, "18");
             } else if (opt.equals("19")) {
-                settings.put(CompilerOptions.OPTION_Source, CompilerOptions.VERSION_19);
+                settings.put(CompilerOptions.OPTION_Source, "19");
             } else if (opt.equals("20")) {
                 // Constant not available in latest ECJ version that runs on
                 // Java 11.
@@ -392,11 +392,11 @@
                 settings.put(CompilerOptions.OPTION_TargetPlatform, CompilerOptions.VERSION_17);
                 settings.put(CompilerOptions.OPTION_Compliance, CompilerOptions.VERSION_17);
             } else if (opt.equals("18")) {
-                settings.put(CompilerOptions.OPTION_TargetPlatform, CompilerOptions.VERSION_18);
-                settings.put(CompilerOptions.OPTION_Compliance, CompilerOptions.VERSION_18);
+                settings.put(CompilerOptions.OPTION_TargetPlatform, "18");
+                settings.put(CompilerOptions.OPTION_Compliance, "18");
             } else if (opt.equals("19")) {
-                settings.put(CompilerOptions.OPTION_TargetPlatform, CompilerOptions.VERSION_19);
-                settings.put(CompilerOptions.OPTION_Compliance, CompilerOptions.VERSION_19);
+                settings.put(CompilerOptions.OPTION_TargetPlatform, "19");
+                settings.put(CompilerOptions.OPTION_Compliance, "19");
             } else if (opt.equals("20")) {
                 // Constant not available in latest ECJ version that runs on
                 // Java 11.