diff --git a/libs/kotlin-reflection/build.gradle b/libs/kotlin-reflection/build.gradle
index 0f3f444b76e..99c50b376ee 100644
--- a/libs/kotlin-reflection/build.gradle
+++ b/libs/kotlin-reflection/build.gradle
@@ -26,7 +26,7 @@ dependencies {
     compileOnly "co.paralleluniverse:quasar-osgi-annotations:$quasarVersion"
     implementation platform("net.corda:corda-api:$cordaApiVersion")
 
-    testCompileOnly "org.jetbrains:annotations:$jetbrainsAnnotationsVersion"
+    testCompileOnly 'org.jetbrains:annotations'
     testImplementation "org.assertj:assertj-core:$assertjVersion"
     testImplementation "org.junit.jupiter:junit-jupiter-params:$junit5Version"
     testRuntimeOnly "org.jetbrains.kotlinx:kotlinx-metadata-jvm:$kotlinMetadataVersion"
diff --git a/libs/kotlin-reflection/src/main/kotlin/net/corda/kotlin/reflect/impl/KotlinClassImpl.kt b/libs/kotlin-reflection/src/main/kotlin/net/corda/kotlin/reflect/impl/KotlinClassImpl.kt
index 68e941a8c74..a598271cefd 100644
--- a/libs/kotlin-reflection/src/main/kotlin/net/corda/kotlin/reflect/impl/KotlinClassImpl.kt
+++ b/libs/kotlin-reflection/src/main/kotlin/net/corda/kotlin/reflect/impl/KotlinClassImpl.kt
@@ -380,6 +380,7 @@ private fun <T : Any> Metadata.forKotlinType(
         is KotlinClassMetadata.Class -> KotlinClassImpl.KmClassType(clazz, klazz, pool, km.toKmClass())
         is KotlinClassMetadata.FileFacade -> KotlinClassImpl.KmPackageType(clazz, klazz, pool, km.toKmPackage())
         is KotlinClassMetadata.MultiFileClassPart -> KotlinClassImpl.KmPackageType(clazz, klazz, pool, km.toKmPackage())
+        null -> throw IllegalArgumentException("Incompatible Kotlin metadata version '${metadataVersion.joinToString(".")}'.")
         else -> throw IllegalArgumentException("Unsupported Kotlin class type: $km")
     }
 }
diff --git a/osgi-framework-api/build.gradle b/osgi-framework-api/build.gradle
index 38a10689602..416f2fdbd97 100644
--- a/osgi-framework-api/build.gradle
+++ b/osgi-framework-api/build.gradle
@@ -5,5 +5,5 @@ plugins {
 dependencies {
     compileOnly platform("net.corda:corda-api:$cordaApiVersion")
     compileOnly 'org.osgi:osgi.core'
-    compileOnly "org.jetbrains:annotations:$jetbrainsAnnotationsVersion"
+    compileOnly 'org.jetbrains:annotations'
 }