Just use silicone grease, its cheap at plumbers merchants, wipe round the soldered joint before shrinking the tube, or smear on connector pins. Dielectric grease has its place but not ideal for our applications. I have cut and pasted the reason below.
"It is important to note that dielectric grease will melt silicone rubber over time, and thus should not be used on connectors, such as o-rings, that are made of this rubber.
While the indicated use of dielectric grease calls for it to be used only on the non-metal parts of a connection, it has been shown to be effective at preventing corrosion when applied directly to the metal connectors as well. Care should be taken when using it in this way, because this application can, in some instances, cause the connection to stop working. A common reason for such a failure is that the grease has not been pushed entirely out of the way between the two points of contact."[/I]