1.Open minecraft.jar with winrar.
For windows its located at: %appdata%\.minecraft\bin
For others (I only have windows so this may be incorrect) %appdata%\roaming\.minecraft\bin
2.Find a folder called title
3.Open splashes.txt
4.Edit to your liking.
5. When it asks if you want to update the archive with the new changes made (or something like that) click yes.
For windows its located at: %appdata%\.minecraft\bin
For others (I only have windows so this may be incorrect) %appdata%\roaming\.minecraft\bin
2.Find a folder called title
3.Open splashes.txt
4.Edit to your liking.
5. When it asks if you want to update the archive with the new changes made (or something like that) click yes.
try deleting META-INF folder in the minecraft.jar.