Hello Ruscombe,
I have read this query several times and my mind for some peculiar reason thought "surname". I have just noticed that Jacoleum is the forename. It may help cast some light on this interesting query if you would post the family surname. I feel it may be a misspelling - possibly a French name like Jacques but the "leum" added to Jaco has me puzzled. The thought has struck me that the cleric who completed the Baptismal record had overindulged the previous night and misheard the child's parents say the three words "Jack or Liam".
I hope others will now have second thoughts and make some suggestions
Best Wishes, Christopher