I'm trying to upgrade to Kotlin 1.4, but I'm getting strange problems with jar's in classpath

w: Runtime JAR files in the classpath should have the same version. These files were found in the classpath:
    /home/maio/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-reflect/1.4.0/aa2101a19d8688e368ae6e35e8967550ced73884/kotlin-reflect-1.4.0.jar (version 1.4)
    /home/maio/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-stdlib-jdk8/1.4.0/e3765b66f0610afc92053ff1a93a87a544fca2b/kotlin-stdlib-jdk8-1.4.0.jar (version 1.4)
    /home/maio/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-stdlib-jdk7/1.3.72/3adfc2f4ea4243e01204be8081fe63bde6b12815/kotlin-stdlib-jdk7-1.3.72.jar (version 1.3)
    /home/maio/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-stdlib/1.3.72/8032138f12c0180bc4e51fe139d4c52b46db6109/kotlin-stdlib-1.3.72.jar (version 1.3)
    /home/maio/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-stdlib-common/1.3.72/6ca8bee3d88957eaaaef077c41c908c9940492d8/kotlin-stdlib-common-1.3.72.jar (version 1.3)

Any idea why this may happen?

❤️ @no - my Googling skills failed me... could have saved few hours by asking here right away 😄